State Profiles

For each state with a preschool education program, we include one page with a description of the state’s program, followed by a page with data on the program’s key features, focusing on access, quality, and resources. 

The first page for each state begins with two sets of line graphs. The first set shows percentages of the state’s 3-year-olds and 4-year-olds enrolled in state-funded preschool in the state. The second set shows the state’s spending per child enrolled in state-funded preschool. Both sets of line graphs depict changes in state preschool over time, from fiscal year 2002 (which corresponds to the 2001-2002 school year) through fiscal year 2023 (which corresponds to the 2022-2023 school year). Most of the data used for comparison purposes come from NIEER’s previous Yearbooks, although spending figures are adjusted for inflation and represent 2023 dollars. In addition, there are some exceptions in cases where states revised data or reported data differently. The percent of children enrolled is calculated using Census estimates of 3- and 4-yearold children in each state. For the 2020-2021 school year, in response to the impact of COVID-19 on preschool enrollment, there is a dark orange dot on the spending per child line graph which shows the state pre-K spending per the estimated full enrollment equivalent. This is an estimate of what spending per child would have been if the program was fully enrolled. This was not done again in 2021-2022 or 2022-2023. 

Following the line graphs is a brief narrative providing information on the main features of the state’s program(s). This includes an overview of preschool enrollment, spending and quality; any new developments; details such as the program’s history, the types of settings in which state-funded preschool can be offered, and eligibility criteria. In many cases, the narrative also describes unique or particularly interesting aspects of the state’s program(s) that may not be highlighted elsewhere in the report, as well as expected changes for the 2023-2024 school year. Some descriptive information in the narratives was originally based on information found in the reports Seeds of Success from the Children’s Defense Fund and Quality Counts 2002 from Education Week. 

For the 44 states with preschool programs and the District of Columbia, the bottom of the first page of each state profile presents four numbers showing the state’s ranking on the following measures:

• The percentage of the state’s 4-year-old population enrolled in the state’s preschool program (Access Rankings – 4-Year-Olds) 
• The percentage of the state’s 3-year-old population enrolled in the state’s preschool program (Access Rankings – 3-Year-Olds) 
• State expenditures per child enrolled in the program (Resources Rankings – State Spending)
• All reported expenditures per child enrolled in the program, including local and federal spending as well as state spending (Resources Rankings – All Reported Spending).

Federal COVID-19 relief funding used for preschool is also included in the State expenditure per child calculation again this year.

The All Reported Spending ranking often provides a more complete picture of preschool spending in states using local and federal funding sources than the State Spending ranking alone. Because states vary in their ability to report spending from these other sources, however, this ranking is imperfect and sometimes underestimates total spending.

The bottom of the first page of each state profile (including Guam) also presents a box indicating the total number of quality standards benchmarks met.

California, Connecticut, Hawaii, Iowa, Louisiana, Massachusetts, Minnesota, Oregon, Pennsylvania, Virginia, and Washington each have more than one distinct preschool education initiative. Therefore, information is presented slightly differently for these states and is explained on their individual profiles.

State profile pages are also given for the six states that did not fund preschool education programs in the 2022-2023 school year. For these states, the table of quality standards is omitted. These profiles do report enrollment data for special education and federally funded Head Start, however. In addition, data on per-child spending for K–12 education and federal Head Start are included. Profile pages are also included for U.S. territories that do not offer “state-funded” preschool (American Samoa, Commonwealth of the Northern Mariana Islands, Palau, Puerto Rico, and the Virgin Islands). For these five territories, a narrative is provided, as is information about Head Start and special education.

The following sections provide an overview of information contained in the data tables on the state profile pages and explain why these elements are important. Data in the tables are for the 2022-2023 school year except where otherwise noted.

The Access data table begins with the total state preschool enrollment, which is the number of children of all ages enrolled at a specific point in time. Following that is the percentage of school districts (or other local education authorities, such as counties or parishes) providing state-funded preschool programs. This information shows the extent of the initiative’s geographic coverage. Next, the table shows what, if any, income requirement is used in determining eligibility for the program.

Data on the minimum hours of operation (hours per day and days per week) and operating schedule (academic or full calendar year) are shown as additional measures of access because working parents may find it difficult to get their children to and from programs that operate only a few hours a day or week. The amount of time children participate in a preschool program also matters for other reasons, such as influencing the program’s effects on children’s development and learning.

The Access data table also shows enrollment of 3- and 4-year-old children in two federally funded programs: preschool special education and Head Start. New in 2022-2023, the special education enrollment total includes only children in school-or center-based settings and also includes 5-year-olds not yet in kindergarten. The Head Start enrollment total includes children in the American Indian/Alaskan Native and Migrant & Seasonal Head Start programs where applicable. The final item in the table reports how many children ages three and four years old are participating in Head Start through state supplemental funds.

Two Access pie charts illustrate the percentages of the state’s 3- and 4-year-olds enrolled in the state-funded preschool program(s), special education, Head Start, and Other Public ECE programs. The remaining children are categorized as enrolled in “Other/None.” These children may be enrolled in another type of private or publicly funded program (e.g., state-subsidized child care) or may not be attending a center-based program at all. “Other public” was new for 2021-2022 and includes children enrolled in locally, city, or district-funded preschool programs (outside of state-funded preschool). Only ten states were able to report this information. We calculated an unduplicated count for special education enrollment in order to more accurately represent the percentage of children served in the state. The special education percentage in the pie chart represents children who are in school- or center-based special education but not enrolled in Head Start or state preschool programs. We also calculated an unduplicated count for Head Start enrollment in order to avoid double counting Head Start children enrolled in state-funded preschool. For the states that were able to report this information, the Head Start percentage does not include children also enrolled in state-funded preschool.

State policies in critical areas related to quality are shown in the Quality Standards Checklist table. For each policy area, states receive a checkmark when their policy meets or exceeds the related benchmark standard. The first column in the Quality Standards Checklist table lists the policy that is being evaluated. The second column presents information about each state program’s requirements regarding each policy. The third column lists the benchmark for each policy—that is, the rigor of the state requirement needed to meet the benchmark. The fourth column depicts whether the state preschool program’s requirements met the benchmark. A box at the bottom of the fourth column displays the total number of benchmarks met by the state program. New, starting in the 2021-2022 report, an “*” indicates that in practice a program did not meet a benchmark even though a policy was in place. For example, a program that required a BA for lead teachers but allowed waivers resulting in a substantial portion of lead teachers not having at least a BA received an “*” next to the check mark and the total number of benchmarks met.

The Quality Standards Checklist represents a set of minimum criteria, established by state policy, needed to ensure the effectiveness of preschool education programs, especially when serving children who are at-risk for school failure. Although the checklist is not intended to be an exhaustive inventory of all the features of a high quality program, each of these research-based standards is essential for setting the groundwork for high quality experiences for children. Meeting all 10 standards does not necessarily guarantee that a program is of high quality, but no state’s prekindergarten policies should be considered fully satisfactory unless all 10 benchmarks are met. Although programs may routinely engage in practices meeting criteria for quality standards, credit is given only when the practices are explicitly required in state policy.

Judgment inevitably plays a role in setting specific benchmarks based on evidence, as research rarely is completely definitive. We have given more weight to the risk of losing substantial benefits by setting benchmarks too low than to the risk of unnecessarily raising costs by setting benchmarks too high, because research has found the benefits of high quality programs to be substantially greater than the costs. In other words, there is more to lose when programs are weak or ineffective. Nevertheless, the original benchmarks were still conceived as minimum standards. The current benchmarks raise the bar somewhat.

Based on advances in research during more than a decade and a half since establishing the original quality standards benchmarks, we have created the current set, which debuted in the 2016 Yearbook. These shifted the focus somewhat from policies regarding classroom structure toward policies that shape classroom processes associated with positive child developmental outcomes. 1 Specifically, the current benchmarks introduced one new quality standards benchmark and made substantial changes or enhancements to three others. Below, we explain each benchmark, along with the evidence and reasoning behind it.

We also describe the criteria used to assess whether state policies meet each benchmark:

Benchmark 1. Early Learning and Development Standards (ELDS). A state’s ELDS specify a program’s goals. Clear and appropriate expectations for learning and development across multiple domains are an essential starting place for quality. 2 States should have comprehensive ELDS covering all areas identified as fundamental by the National Education Goals Panel 3 — children’s physical well-being and motor development, social/emotional development, approaches toward learning, language development, and cognition and general knowledge. Neglecting any of these developmental domains could weaken both short- and long-term effectiveness. 4

To meet the benchmark, ELDS should be comprehensive and specific to preschool-aged children and vertically aligned with state standards for younger and older children so that children’s experiences at each stage build on what has gone before. 5 ELDS also should be aligned with any required child assessments, and sensitive to children’s diverse cultural and language backgrounds. 6 Finally, the state must provide some support for those charged with implementing the ELDS so they understand them, such as professional development and additional resources.

Benchmark 2. Curriculum supports. A strong curriculum that is well-implemented increases support for learning and development broadly, and includes specificity regarding key domains of language, literacy, mathematics, and social-emotional development. 7 To meet the benchmark for curriculum support, states must provide guidance or an approval process for selecting curricula, and support for curriculum implementation, such as training or ongoing technical assistance to facilitate adequate implementation of the curriculum.

Benchmark 3. Teacher degree. To meet the benchmark, state policy must require lead teachers in every classroom to have at least a bachelor’s degree. This follows recommendations from multiple studies by the Institute of Medicine (IOM) and National Research Council (NRC) of the National Academy of Science recommending that preschool teachers have a BA with specialized knowledge and training in early childhood education. 8 Their conclusions are supported by an analysis of what teachers are expected to know and do in order to be highly effective. Also, a comprehensive review finds that teachers with higher educational levels generally provide higher quality educational environments for young children. 9

Much of the research has approached the question of teacher degree requirements incorrectly by assuming that teacher qualifications and other program features act independently, are unconstrained by regulation, and are independent of unmeasured contexts that affect outcomes. 10 When multiple program features are interdependent, benchmarking is a more appropriate approach for identifying the features associated with success. 11 We found no examples of programs that have produced large persistent gains in achievement without well-qualified teachers.

It also follows that teacher qualifications should not be expected to have an effect in isolation. Compensation must be adequate to attract and retain strong teachers, regardless of qualifications requirements. 12 We have not made this part of the benchmark due to the difficulty of ascertaining exactly what “adequate compensation” is for each state—but that does not lessen its importance.

Benchmark 4. Teacher specialized training. Institute of Medicine/National Research Council reports have also emphasized that preschool lead teachers should have specialized preparation that includes knowledge of learning, development, and pedagogy specific to preschool-age children. 13 To meet the benchmark, policy must require specialized training in early childhood education and/or child development. We recognize that early childhood teacher preparation programs are variable. States may wish to consider supports to improve programs offered by their state institutions of higher education and alignment with the state ELDS. 14

Benchmark 5. Assistant teacher degree. All members of a teaching team benefit from preservice preparation. The Child Development Associate (CDA) credential was developed as the entry-level qualification for the field. 15 Other certifications or coursework can provide similar preparation. There has been limited research specific to the qualifications of assistant teachers, but evidence indicates that assistant teacher qualifications are associated with teaching quality. To meet the benchmark, policy must require that assistant teachers hold a CDA or have equivalent preparation based on coursework.

Benchmark 6. Staff professional development. To meet this benchmark both teachers and assistant teachers must be required to have at least 15 hours of annual in-service training. In addition, some professional development must be provided through coaching or similar ongoing classroom-embedded support. Lead and assistant teachers are also required to have annual written individualized professional development plans. Research indicates regular professional learning, including coaching, supports teaching practices related to high quality experiences for children. 16 Individualized professional development focused on helping teachers improve in their own classrooms has been found more effective than traditional workshops and general professional development. 17 Good teachers actively engage in learning and regular professional development, and there is some evidence for a 15-hour threshold. 18

Benchmarks 7 and 8. Maximum class size (20) and staff-child ratio (1:10). These two benchmarks are addressed together as they are highly linked in policy and practice. To meet benchmark 7, class size should be limited to at most 20 children. To meet benchmark 8, classes should be permitted to have no more than 10 children per classroom teaching staff member. Small class size and corresponding teacher-child ratios characterize the most effective programs, even though many studies find weak or no association between these features and effectiveness. 19 Yet, it seems clear that smaller classes and fewer children per teacher enable teachers to interact with each child more frequently, to work with smaller groups, and offer each child more individualized attention, which results in better outcomes. The smaller the class, the easier it is for a teacher to develop a good understanding of each child’s interests, needs, and capabilities.

What may be the best designed large-scale randomized trial of class size for young children to date found substantive and lasting impacts on achievement and educational success for smaller class sizes in kindergarten. 20 Subsequent efforts to reproduce these results through policy changes elsewhere have been far less successful. Again, we note that key policies regarding program features are not independent of other policies, context, and implementation.

A staff-child ratio of 1:10 is lower than in programs found to have the largest persistent effects, but it is generally accepted by professional opinion. A recent meta-analysis suggests an even lower threshold, below 1 to 7.5 (class size of 15), would be better, and that finding is consistent with experimental evidence for kindergarten. 21 On the other hand, at least one program has produced large short-term gains with a maximum class size of 22 and 1:11 staff to child ratio, just outside the benchmarks. 22

Benchmark 9. Screenings and referrals. To meet the benchmark, policies should require that preschool programs ensure children receive vision and hearing screenings and at least one additional health screening; as well as referrals when needed. 23 This benchmark recognizes that children’s overall well-being and educational success involve not only cognitive development but also physical and mental health. 24 This quality standards benchmark no longer assesses provision of support services. Nearly all state-funded pre-K programs have some requirement for parent engagement and support, and we could not set an evidence-based benchmark that differentiated among them based on effectiveness.

Benchmark 10. This benchmark focuses on state requirements regarding a Continuous Quality Improvement System (CQIS). This reflects a shift in focus from compliance to state support for continuous improvement. An effective CQIS operates at local and state levels to ensure that information is gathered regularly on processes and outcomes, and that this information is used to guide program improvement. To meet this benchmark, policy must at a minimum require that (1) data on classroom quality is systematically collected, and (2) local programs and the state both use information from the CQIS to help improve policy or practice. The use of a cycle of planning, observation, and feedback has characterized highly effective programs. 25

The original Quality Standards Checklist required that programs should provide at least one meal per day. While nutritious meals are important, this requirement has been removed from the Checklist because whether a program met the requirement was largely determined by whether the program operated for a half day or full school day.

The table in the Resources section provides the following information: total state spending for the state preschool program; whether a local match, monetary or in-kind, is required; amount of state Head Start spending; state spending per child enrolled in the program; and all reported (local, state, and federal) spending per child enrolled in the program. These measures show various views of the resources dedicated to state preschool programs, which allows for a more complete picture of a state’s commitment to preschool education. For example, a state’s total spending may appear low, but may prove to be high relative to the number of children enrolled. On the other hand, a state with a high total funding level may have a low per-pupil spending level if it enrolls a large number of children. In some states, local communities contribute substantial additional funds to state preschool education by using local funding sources or by leveraging federal funding sources. In such cases, the figure that includes all reported spending is the best gauge of the level of available resources, to the extent that information about local and locally allocated federal spending is available.

The bar chart in the Resources section compares per-child spending in state-funded preschool programs to federal Head Start and K–12 per-child spending. Head Start per-child spending for the 2022-2023 year includes funding only for 3- and 4-year-olds served. Past years’ figures have unintentionally included funds for Early Head Start, which made per-child amounts seem artificially higher (although this has been corrected for the past several years). Different colors indicate the different funding sources (local, state, and federal). Separate colors are used to indicate any TANF funds or federal COVID-19 relief funds that a state directs toward its preschool initiative. While TANF and COVID-19 relief funds are federal dollars, it is the state’s decision to devote these funds to preschool education, as opposed to other purposes. Therefore, TANF and COVID-19 relief funds are including in the “State” funding amount. Data on the amounts of local and federal preschool funds are included in the bar chart when available.

1. Minervino, J. (2014) Lessons from research and the classroom: Implementing high-quality pre-k that makes a difference for young children. Seattle, WA: Bill and Melinda Gates Foundation. Weiland, C. (2016). Launching preschool 2.0: A roadmap to high-quality public programs at scale. Behavioral Sciences & Policy, 2(1). 37-46. Yoshikawa, H., Weiland, C., Brooks-Gunn, J., Burchinal, M., Espinosa, L. M., Gormley, Jr., W. T., Ludwig, J., & et al. (2013). Investing in our future: The evidence base on preschool education. Ann Arbor, MI: Society for Research in Child Development. 
2. Bornfreund, L. A., McCann, C., Williams, C., & Guernsey, L. (2014). Beyond subprime learning: Accelerating progress in early education. Washington, DC: New America Foundation. Bowman, B. T., Donovan, M. S., & Burns, M. S. (Eds.). (2001). Eager to learn: Educating our preschoolers. Washington, DC: National Academy Press. 
3. National Education Goals Panel (1991). The Goal 1 Technical Planning Subgroup report on school readiness. Washington, DC: Author. National Association for the Education of Young Children (2009). 
4. Shonkoff, J. P., & Phillips, D. A. (Eds.). (2000). From neurons to neighborhoods: The science of early childhood development. Washington, DC: National Academy Press. 
5. Kauerz, K., & Coffman, J. (2013). Framework for planning, implementing, and evaluating preK-3rd grade approaches. Seattle: University of Washington, College of Education. Minervino (2014). Tout, K., Halle, T., Daily, S., Albertson-Junkans, L., & Moodie, S. (2013). The research base for a birth through age eight state policy framework. Washington, DC: Alliance for Early Success and Child Trends. 
6. Espinosa, L. M. (2010). Getting it right for young children from diverse backgrounds: Applying research to improve practice. Upper Saddle River, NJ: Pearson Education, Inc. 
7. Burchinal, M. (2018). Measuring Early Care and Education Quality. Child Development Perspectives, 12(1), 3-9. Clements, D. H., & Sarama, J. (2008). Experimental evaluation of the effects of a research-based preschool mathematics curriculum. American Educational Research Journal, 45, 443-494. Frede, E.C. (1998). Preschool program quality in programs for children in poverty. In Barnett, W.S., Boocock, S.S. (Eds.), Early care and education for children in poverty (pp. 77–98). Albany, NY: SUNY Press. Minervino (2014). Phillips, D.A., Lipsey, M.W., Dodge, K.A., Haskins, R., Bassok, D., Burchinal, M.R.,…Weiland, C. (2017). Puzzling it out: The current state of scientific knowledge on pre-kindergarten effects, a consensus statement. Washington, DC: Brookings Institution. Downloaded July 24, 2017 from https://www.brookings.edu/wp-content/uploads/2017/04/consensus-statement_ final.pdf. Weiland (2016). Yoshikawa et al. (2013). 
8. Bowman et al. (2001). Institute of Medicine and National Research Council (2015). Transforming the workforce for children, youth through age 8. Washington, D.C.: The National Academies Press. 
9. Manning, M., Garvis, S., Fleming, C., & Wong, G. T. (2017). The Relationship between Teacher Qualification and the Quality of the Early Childhood Care and Learning Environment: A Systematic Review. Campbell collaboration. Downloaded August 15, 2017 from https://www.campbellcollaboration.org/library/teacher-qualification-and-quality-of-early-childhood-care-and-learning.html 
10. Bogard, K., Traylor, F., & Takanishi, R. (2008). Teacher education and PK outcomes: Are we asking the right questions?. Early Childhood Research Quarterly, 23(1), 1-6. Falenchuk, O., Perlman, M., McMullen, E., Fletcher, B., & Shah, P. S. (2017). Education of staff in preschool aged classrooms in child care centers and child outcomes: A meta-analysis and systematic review. PloS one, 12(8), e0183673. Lin, Y. C., & Magnuson, K. A. (2018). Classroom quality and children’s academic skills in child care centers: Understanding the role of teacher qualifications. Early Childhood Research Quarterly, 42, 215-227. 
11. Bassok, D., Fitzpatrick, M., Greenberg, E., & Loeb, S. (2016). Within- and between-sector quality differences in early childhood education and care. Child Development, 87(5), 1627-1645. 
12. King, E. K., Johnson, A. V., Cassidy, D. J., Wang, Y. C., Lower, J. K., & Kintner-Duffy, V. L. (2016). Preschool teachers’ financial well-being and work time supports: Associations with children’s emotional expressions and behaviors in classrooms. Early Childhood Education Journal, 44(6), 545-553. Whitebook, M., Phillips, D., & Howes, C. (2014). Worthy work, STILL unlivable wages: The early childhood workforce 25 years after the National Child Care Staffing Study. Berkeley, CA: Center for the Study of Child Care Employment. 
13. Institute of Medicine and National Research Council (2015). Also: Bowman et al. (2001). Fukkink, R. G., & Lont, A. (2007). Does training matter? A meta-analysis and review of caregiver training studies. Early childhood research quarterly, 22(3), 294-311. 
14. Early, D. M., & Winton, P. J. (2001). Preparing the workforce: Early childhood teacher preparation at 2-and 4-year institutions of higher education. Early Childhood Research Quarterly, 16(3), 285-306. Whitebook, M., & Ryan, S. (2011). Degrees in Context: Asking the Right Questions about Preparing Skilled and Effective Teachers of Young Children. Preschool Policy Brief. Issue 22. New Brunswick, NJ: National Institute for Early Education Research. 
15. Bowman et al. (2001). Institute of Medicine and National Research Council (2015). Han, J., & Neuharth-Pritchett, S. (2010). Beliefs about classroom practices and teachers’ education level: An examination of developmentally appropriate and inappropriate beliefs in early childhood classrooms. Journal of Early Childhood Teacher Education, 31(4), 307-321. Heisner, M. J., & Lederberg, A. R. (2011). The impact of Child Development Associate training on the beliefs and practices of preschool teachers. Early Childhood Research Quarterly, 26(2), 227-236. Kagan, S. L., & Cohen, N. E. (1997). Not by chance: Creating an early care and education system for America’s children [Abridged report]. New Haven, CT: Bush Center in Child Development and Social Policy, Yale University. 
16. Biancarosa, G., Bryk, A. S., & Dexter, E. R. (2010). Assessing the value-added effects of literacy collaborative professional development on student learning. The Elementary School Journal, 111(1), 7-34. Clements, D. H., & Sarama, J. (2008). Experimental evaluation of the effects of a research-based preschool mathematics curriculum. American Educational Research Journal, 45, 443-494. Hawley, W. & Valli, L. (1999). The essentials of effective professional development: A new consensus in L. Darling-Hammond & G. Sykes (Eds.). Teaching as the Learning Profession. Handbook of Policy and Practice, Jossey-Bass Publishers, San Francisco. Institute of Medicine and National Research Council (2015). Minervino (2014). Phillips et al. (2017). Pianta et al. (2009). Weber, R. & Trauten, M. (2008). A review of the research literature: Effective investments in child care and early education profession. Oregon State University, Family Policy Program, Oregon Childcare Research Partnership. Whitebook, M., & Bellm, D. (2013). Supporting teachers as learners: A guide for mentors and coaches in early care and education. Washington, DC: American Federation of Teachers. Weiland (2016). Yoshikawa et al. (2013). 
17. Pianta, R., Downer, J., & Hamre, B. (2016). Quality in early education classrooms: Definitions, gaps, and systems. Future of Children, 26, 119-137. Weiland (2016). Yoshikawa et al. (2013). 
18. Bowman et al. (2001). Frede (1998). Egert, F., Fukkink, R. G., & Eckhardt, A. G. (2018). Impact of In-Service Professional Development Programs for Early Childhood Teachers on Quality Ratings and Child Outcomes: A Meta-Analysis. Review of Educational Research, 0034654317751918. Frede (1998). Kraft, M. A., Blazar, D., & Hogan, D. (2016). The effect of teacher coaching on instruction and achievement: A meta-analysis of the causal evidence. Review of Educational Research. Landry, S. H., Anthony, J. L., Swank, P. R., & Monseque-Bailey, P. (2009). Effectiveness of comprehensive professional development for teachers of at-risk preschoolers. Journal of Educational Psychology, 101(2), 448. Rudd, L. C., Lambert, M. C., Satterwhite, M., & Smith, C. H. (2009). Professional development + coaching = enhanced teaching: Increasing usage of math mediated language in preschool classrooms. Early Childhood Education Journal, 37(1), 63-69. Whitebook, Howes, & Phillips (1989) found that teachers receiving more than 15 hours of training were more appropriate, positive, and engaged with children in their teaching practices. 
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21. Evidence suggesting value to lower thresholds comes from Bowne, J., Magnuson, K. A., Schindler, H. S, Duncan, G. J., & Yoshikawa, H. (2017). A meta-analysis of class sizes and ratios in early childhood education programs: Are thresholds of quality associated with greater impacts on cognitive, achievement, and socioemotional outcomes? Education Evaluation and Policy Analysis. 39(3), 407-428. 
22. Weiland, C., & Yoshikawa, H. (2013). Impacts of a prekindergarten program on children’s mathematics, language, literacy, executive function, and emotional skills. Child Development, 84(6), 2112-2130. 
23. For some children, preschool provides the first opportunity to detect vision, hearing, and health problems that may impair a child’s learning and development. This opportunity should not be missed. Meisels, S. J., & Atkins-Burnett, S. (2000). The elements of early childhood assessment. In J. P. Shonkoff & S. J. Meisels (Eds.). Handbook of early childhood intervention (pp. 231-257). New York: Cambridge University Press. Tout et al. (2013). 
24. Blair (2002). School readiness: Integrating cognition and emotion in a neurobiological conceptualization of children’s functioning at school entry. American Psychologist, 57, 111-127. Janus, M., & Duku, E. (2010). The school entry gap: Socioeconomic, family, and health factors associated with children’s school readiness to learn. Early Education and Development, 18, 375-403. 
25. Barnett, W. S., Frede, E. C. (2017). Long-term effects of a system of high-quality universal preschool education in the United States. In Blossfeld, H.-P., Kulic, N., Skopek, J., Triventi, M. (Eds.), Childcare, early education and social inequality: An international perspective (pp. 152–172). Cheltenham, UK: Edward Elgar. Bowman et al. (2001). Derrick-Mills, T., Sandstrom, H., Pettijohn, S., Fyffe, S., & Koulish, J. (2014). Data use for continuous quality improvement: What the Head Start field can learn from other disciplines, a literature review and conceptual framework (OPRE Report 2014-77). Washington, DC: Office of Planning, Research and Evaluation, Administration for Children and Families. U.S. Department of Health and Human Services. Egert et al. (2018). Institute of Medicine and National Research Council (2015). Minervino (2014). Weiland (2016).