Ostensibly, gifted programs exist to provide advanced educational experiences to children who would be unchallenged in a regular classroom setting. According to theory, a bright child would receive a more advanced educational and develop their potential earlier or to a more extensive level than they would in a typical program.

But these programs can have consequences for other stakeholders: the parents and the schools. In a perfect world, the benefits and preferences of parents, school personnel, and the child would all coincide, but they often do not. Gifted programs can impose varying costs and benefits on each of these stakeholders. The same is true of costs.

In this blog post, I will do a basic cost-benefits analysis of varying gifted programs. This blog post builds on the work of Frisvold (2015), who examined the costs of different types of academic acceleration (e.g., grade skipping, single-subject acceleration). However, Frisvold (2015) did not assess benefits of different interventions or reach a conclusion about whether those would outweigh the costs. I hope that my efforts can serve as a starting point for understanding policy choices — until someone with more financial expertise can perform a more thorough, accurate analysis.

There are four types of costs and/or benefits that gifted education programs could produce: (1) academic; (2) financial; (3) social/emotional; and (4) other costs or benefits, such as prestige and stimulating a child’s interest. I will only evaluate academic and financial benefits and costs because the social/emotional and other benefits are either hard to quantify in financial terms, or there is not enough research to make much of a judgment. Also, note that only students receive academic benefits, while all three parties (i.e., students, parents, and school systems) can experience financial costs and/or benefits.

Enrichment Programs

Enrichment programs are the weakest form of gifted education programs. They do not replace the standard curriculum for a gifted child. Rather, they “enrich” it by providing a deeper level of engagement with the the material. Many enrichment programs occur after school hours in the form of field trips, extracurricular activities, and arts opportunities (e.g., a school band, an after-school play). Others are offered during school hours as a “pull-out” program in which the gifted child leaves the regular classroom temporary to participate in the enrichment program.

Costs and Benefits to the Student

A recent meta-analysis on the effects of enrichment programs (Kim, 2016) found that participation in an enrichment program shows strong academic (g = .96) and social/emotional (g = .55) effects for children. However, this meta-analysis suffers from obvious publication bias, and these effect sizes are unrealistically high (Warne, 2016a). I cannot find any studies on the financial benefits that enrichment programs may bring children.

Enrichment programs are very poorly studied. Even when the studies occur, they tend to be small-scale and conducted by people with a vested interest in the enrichment program (e.g., the program’s creators). Additionally, the methodology tends to be shoddy. In Kim’s (2016) meta-analysis, for example, none of the studies were randomized control trials. The median sample size was 88 for the pre/posttest studies and 65 for the quasi-experiments. This is not a strong body of research. We really do not know much about whether enrichment programs help children academically (Warne, 2016a).

From a theoretical perspective, enrichment programs should provide very little benefit to students. Wai (2015) and his colleagues (Wai et al., 2010) have discussed the concept of the “educational dose,” which is a measure of the strength of an academic intervention (see also Gallagher, 2000; Warne, 2016b). By any standard, enrichment programs have a very weak educational dose. At best, they provide some mild stimulation for a few hours per week. There is no reason to expect large benefits from such a paltry educational program.

On the other hand, the costs of enrichment programs to students are likely low also. Again, I cannot find any research on the topic, but I cannot see how participating in enrichment programs could incur academic or financial costs to students.

In general, I see enrichment programs as providing a neutral effect for students. There seem to be small or no benefits . . . but they also produce no costs for students.

Costs and Benefits to the Parents

There is even less research on costs and benefits of enrichment programs to parents. However, some assumptions are reasonable. Enrichment programs during school hours generally cost parents nothing and should provide no discernable financial benefits to parents. On the other hand, many extracurricular activities require a participation fee (though this is often waived for low-income families). For parents, I see enrichment programs as generally having no benefits, but also no (or low) costs.

Costs and Benefits to Schools

At first glance, providing an enrichment program where there was none before should be a financial negative for schools. Indeed, Frisvold (2015, p 63) identified enrichment programs (in the form of extracurricular activities) as having one of the highest costs of the 20 gifted education interventions he investigated.

But schools do not always pay this cost directly, and this is where the cost/benefit analysis gets complicated. In some states (such as Florida and Ohio), the state provides funds earmarked for gifted education services that can be used for enrichment programs. In many of these states, the policy for this funding is “use it or lose it,” and the funds would not be available to a school if not used for gifted education programs. In other states (such as California and New York), there are no dedicated funds for gifted education, and any programs must come out of the school’s or district’s general budget. Therefore, in some states, having the gifted program is financially neutral or maybe a slight positive for the school or district. In other states, though, enrichment programs have financial costs for schools and districts.

There are other considerations for schools, though. In some areas, gifted programs are used to attract middle- and upper-class parents to enroll their children in the district or school. Because most state funding for schools is allocated on a per-pupil basis, it only takes a small increase in school enrollment for an enrichment program to pay for itself. This pressure should be most acute in areas where school competition is most prevalent, such as states where charter schools and private school vouchers are available and geographic regions where parents can easily move to a new school district nearby. Again, this is hard to quantify with my level of expertise, but it is important to consider.

In general, the benefits of enrichment programs to schools are complex. Depending on the circumstances, an enrichment program could be a net negative, but in other circumstances, it could provide positive financial benefits for schools.

Overall costs and benefits

Generally, I see enrichment programs as potentially benefiting schools most and providing small or neutral impacts on students and parents. However, there is variability on this point, and for some schools enrichment programs may be net financial negative.

Single-Subject Acceleration

The second-most common gifted intervention is single-subject acceleration, which is a program that gives a gifted child an advanced curriculum in one subject and a typical educational program in other subjects. The most popular form of single-subject acceleration in the United States is the College Board’s Advanced Placement (AP) courses, which allow students to take an introductory-level college course and demonstrate their proficiency by passing a standardized test (see Warne, 2017a, for more information about the AP program). Another popular single-subject option in high school is concurrent enrollment, which allows a student to attend a class taught by a local college or university and earn both high school and college credit.

Single-subject acceleration also exists at the elementary and middle school levels. In some schools, a child can attend a higher grade for part of the day to get advanced instruction in one topic. Likewise, in middle school, it is not unusual for a child to be placed in a class that is generally populated by older peers (e.g., a 7th grader enrolled in algebra).

Costs and Benefits to the Student

Academically, single-subject acceleration provides more academic benefits than enrichment programs, which is consistent with the higher “educational dose” that single-subject acceleration provides. In Rogers’s (2015, pp. 26-27) meta-analysis, AP, concurrent enrollment, and other single-subject acceleration programs increased academic achievement by d = .41 to .60. Unlike the effect sizes for the enrichment meta-analysis, these values are realistic. When my coauthors and I controlled for over 70 covariates, we found that students in AP classes had much higher achievement scores than similar students in non-AP classes (Warne et al., 2015). The largest gains (up to d = .86), though, were for students who took the AP test (especially if the student passed the test).

There is much less research on the financial benefits of single-subject acceleration. Most of the research that exists, though, focuses on the Advanced Placement program. This is likely because the College Board advertises the AP program as a way to save money by shortening the time it takes to graduate from college. However, Klopfenstein (2010) found that students who pass AP courses were not more likely to graduate from college in less than four years, but concurrent enrollment students were.

The proportion of college students who save tuition by graduating early is tiny, though. In Klopfenstein’s (2010) sample, students who graduated in three years were only 2.4% of all college students and 1.2% of those who graduate in five years or less. Concurrent enrollment clearly does not cause large numbers of students to save money by graduating early.

But those who do graduate from college in just three years save a full year’s worth of tuition and other expenses and start earning a full-time income one year earlier than they would otherwise. The average cost of attending a four-year public university in the U.S. is $19,250. If that new graduate earns $45,000 in their first year after college, then the total financial benefit of single-subject acceleration is nearly $65,000. Students graduating with degrees in lucrative majors (like engineering) would see an even larger financial benefit.

Generally for students, the academic effects of single-subject acceleration seem robust and worthwhile. For most students, the financial benefit of single-subject acceleration is neutral, but for the small percentage who graduate early, single-subject acceleration can be a financial bonanza. In general, the financial benefits of single-subject acceleration are neutral, but can outweigh the costs for students.

Costs and Benefits to the Parents

Most single-subject interventions are free to parents. They may incur some costs, though, if a child requires transportation (e.g., an elementary school student needs a ride to a middle school to take pre-algebra each day). Also, parents often pay AP exam fees ($97 per test in 2023), though some examinees get a reduced fee for economic hardship or have their fee subsidized by their district or state.

To the extent that parents pay for their child’s college education, then the financial benefits of single-subject acceleration track with the child’s benefits. However, parents don’t receive the extra year of income that the child earns if a child graduates from college one year early.

Therefore, the financial benefits of single-subject acceleration can be slightly negative, neutral, or positive for parents, depending on circumstances. However, the financial benefits are not as strongly positive as they are for the student.

Costs and Benefits to Schools

Again, this is where the cost-benefit analysis of a gifted program gets more complicated. Some forms of single-subject acceleration are already in place (e.g., a mixed-age science course in high school) or are very inexpensive to implement (such as allowing a child to visit an older grade on a regular basis to receive instruction in a single subject). In these cases, the financial costs of single-subject acceleration are neutral.

Other forms of single-subject acceleration are much more expensive. The College Board estimates that it costs $2,050 to $11,650 to offer a single AP class to 25-30 students (the equivalent of $68-466 per student). Some of these costs are one-time or upfront costs, and others carry over from year to year. Additionally, some of the costs would be spent anyway. (For example, if chemistry lab equipment would be purchased for a non-AP class anyway, then this is not a cost of offering AP.)

Another consideration is that many states and school districts subsidize the fee for an AP test for some or all students. For example, in Minnesota, the state pays the AP exam fee for low-income students and nearly half of the fee for all other students. In 2012, fee subsidies in Minnesota totaled $3 million for the state ($82 per student).

There are other costs that some schools incur for offering AP classes. Florida is particularly noteworthy for its generous state subsidies for the AP program. In 2008-2009, the subsidies totaled about $53 million (a cost of about $400 per student). This money goes to school funding bonuses, teacher bonuses, student exam fees, teacher training, and more.

Florida is an anomaly in this respect. Compared to most states, the costs of concurrent enrollment are higher for governments than the AP program is. In Utah, concurrent enrollment costs the state $11.9 million for 36,335 students. That is the equivalent of a cost of $328 per student — pricier for schools than most AP classes.

Despite the expenses, schools do receive some benefits for AP. In Florida, state subsidies for AP were $30 million more than the costs to schools to offer those classes until the funding mechanism was changed. Even outside of a subsidy system, AP can still benefit schools, in spite of the costs. Many middle- and upper-class parents see the number of AP courses as a marker of prestige for a school (Klugman, 2013), and offering a large number of classes can be a way to attract enrollment. Just like for enrichment programs, it does not take a many students enrolling in a school for its AP program to pay for itself.

I cannot find any information about the financial benefits to schools for offering concurrent enrollment or other forms of single-subject acceleration. Because concurrent enrollment is more expensive, I anticipate that its costs are less likely to outweigh any financial benefits for schools. Other single-subject acceleration is probably neutral–especially only offered to a single child–or slightly positive (e.g., if honors classes in a single subject in elementary or middle school incentivize enrollment).

AP is the most popular program that gifted students participate in, but it’s also one of the most expensive for schools to implement.

Magnet and Standalone Gifted Programs

Magnet and standalone gifted programs are educational programs in which students attend a self-contained program that offers more advanced instruction for the entire school day. Some of these programs take the form of a special class within a neighborhood school; others are magnet programs that draw students from throughout a school district. Magnet and standalone programs are what most people imagine when they hear about “gifted programs.”

Costs and Benefits to Students

The data on the academic impact of magnet or standalone gifted programs is conflicted. While Rogers (2007) found noticeably strong effects (d = .49) in a meta-analyses, well-designed, large-scale studies tend to find that gifted programs provide few or no gains in academic compared to a typical educational program (e.g., Bui et al., 2014). There are exceptions, though (e.g., Card & Giuliano, 2016). If forced to take a position, I would say that the typical magnet or standalone gifted program has neutral or slightly positive academic benefits for students.

Like the other programs analyzed above, there are no financial costs to students enrolled in a magnet or standalone program. I cannot find any research on the financial benefits to students of magnet or standalone programs. I imagine that there are a few magnet high schools that indirectly provide financial benefits to their students by giving them networking opportunities and a highly prestigious training regimen (such as New York City’s famous LaGuardia High School of Music & Art and Performing Arts). Others may be financially beneficial because their staff is highly experienced at getting students admitted into prestigious universities.

However, these are rare cases. Most standalone or magnet programs probably offer no financial benefit to their students. Many of them end before high school, and most provide the same curriculum — just with more detail — as typical classes.

In a few special cases, standalone or magnet gifted programs probably provide notably large financial benefits for students. But in most cases, their financial impact is neutral for students.

Costs and Benefits to Parents

I can find no research on the financial costs and benefits of magnet or standalone gifted programs for parents. For some magnet programs, parents may be responsible for their child’s transportation to school, and that can be a financial cost for some parents. Some programs may also have special fees associated with them if there are costs associated with special educational opportunities for the students in the program (e.g., extra field trips).

Likely, the costs to parents of a magnet or standalone gifted program are neutral or slightly negative. More research is needed on this point, though.

Costs and Benefits to Schools

A standalone program within a neighborhood school probably has neutral costs because the number of classes, teachers, and students at the school does not change in this program. In other words, the same students attend the school, but a standalone gifted program shuffles some high performers to the same classroom within their grade.

Magnet programs, though, are more complicated in their costs and benefits for schools. If a magnet school requires a new facilities and equipment that would not ordinarily be available and teachers with special training or experience, then a magnet program may have massive costs to a school district. This scenario probably applies to many performing arts and advanced science magnet high schools.

The typical magnet gifted program, though, exists at the elementary and/or middle high school level in a building that also houses typical students attending the building as their neighborhood school. Many districts house these gifted programs in buildings that have low enrollment for various reasons. By housing the magnet program at an under-attended school, many districts avoid closing the building. By moving students away from schools with higher enrollment, some districts may also avoid incurring the cost of erecting another building elsewhere. In this scenario, a gifted magnet program is a major financial benefit to the school district. The costs would probably be trivial in comparison.

There is also the potential benefit to standalone and magnet programs that exists for other programs: the prospect of luring and/or retaining students in a district may be a financial benefit for schools. In general, though, magnet and standalone magnet programs probably give schools a neutral or positive financial benefit. But in isolated cases a magnet school may be a major financial cost for school districts.

Full-Grade Acceleration (i.e., Grade Skipping)

The last gifted program or intervention I will analyze here is full-grade acceleration. Commonly called grade skipping, this involves advancing a child to a grade before they normally would advance with their age peers. Most grade skips occur after the school year ends (e.g., a child finished 3rd grade before moving on to 5th grade when the new school year begins). However, sometimes children skip a grade mid-year. The vast majority of children who skip a grade do so only once, and this analysis will not consider multiple skips. Of the four interventions I discuss in this post, this one has the strongest “educational dose” because the child is in a more intensive academic program (i.e., a higher grade) every day for the rest of their K-12 educational career.

Costs and Benefits to Students

Unlike the research on other gifted education interventions, there is extensive research on the impacts of grade skipping, and the results are uniformly positive (Assouline et al., 2015; Miravete, in press). Compared to other interventions for gifted children, full-grade acceleration is one of the most effective ways to increase a gifted child’s academic achievement (Rogers, 2007, 2015). The research could be improved (Miravete, in press; Warne & Liu, 2017), though I doubt that better methodologies will overturn the general finding that grade skipping provides academic benefits to gifted children because it is one of the most consistent findings in all of educational psychology.

There are no known costs that a child incurs when they receive full-grade acceleration. However, there is research on its financial benefits. In two studies of archival data, I found that grade skippers earned -2.02% to 9.35% more annually as adults (Warne, 2017b; Warne & Liu, 2017), and another researcher has found similar results (McClarty, 2015). It is important to recognize, though, that there was a lot of variation in the contributing data and that the studies do not permit the conclusion that grade skipping causes people to earn more money as adults. But even if the causal impact of grade skipping on income were zero, children who finish their education one year early can benefit financially by earning an additional year of income as an adult.

On the other hand, if the child pays for some or all of their college education, then a grade skip can incur some costs. This is because they will have one year less to earn and save money before enrolling in college. As a result, they may be required to take out more student loans than a child of the same age who graduates from high school at age 18.

Of all the gifted education interventions I consider, grade skipping has the most uncertain costs for students. In a worst-case scenario, a child’s extra year of earning and any greater lifetime earnings will not compensate for the burden of extra student loans. In a best-case scenario, the child has their college fully paid for via their own earnings, scholarships, and the contribution of their parents, and the grade skip provides a massive lifelong payoff.

Costs and Benefits to Parents

Costs of a grade skip to parents have not been researched. During the child’s K-12 years, the financial costs are probably zero. Afterwards, the costs will vary. For parents who shoulder some or all of the expense of their child’s college education, a grade skip may have a financial cost under two scenarios. The first is if the child has less time to earn money to pay for college and the parent plans on paying for the remaining costs. The second scenario is if the parent must borrow more money to cover the cost of their child’s education because the parent had one year less to save.

On the other hand, parents who do not need to contribute financially to their children’s education — or who do not plan to — will incur no financial liability from their child’s grade skip. Overall, full-grade acceleration provides no financial benefits and either neutral or strongly negative costs to parents.

Costs and Benefits to Schools

The financial costs of full-grade acceleration are large for school districts. In most states, schools are funded (at least partially) based on the number of students that they enroll. The amount of money spent per child varies from $8,272 (in Idaho) to $25,519 (in New York). Grade skipping a child means that a school district does not receives that amount of money for one year. For a district, this cost is delayed until the year when the child would have typically graduated from high school, but it is still there.

Some of this money comes from the state, though. From the state’s perspective, a grade skip is a financial benefit because the state does not have to pay anything for one year of the child’s K-12 education.

Indeed, states could save a lot of money by incentivizing grade skipping. Only 0.25% of school school children skip a grade in a given year (Warren et al., 2014), and fewer than 3% ever skip a grade (Warne, 2017b). About 20-25% of students could skip a grade at some point in their K-12 career (based on the percentage of students each year who meet or surpass all four of the ACT’s college readiness benchmarks). If even 10% of all students were to skip a grade, then states could eventually save nearly $50 billion per year (based on 49.5 million public school children and an average expenditure of $13,494 per student and only 2.5% of those currently skipping a grade).

Thus, the costs and benefits of full-grade acceleration to school systems depends: for districts, a grade skip has a definite financial cost; for states, a grade skip is a definite financial benefit.


In summary, the financial and costs and benefits of gifted programs vary for different stakeholders. I have summarized the post in the table below.

EnrichmentSingle-Subject AccelerationStandalone/Magnet ProgramFull-grade Acceleration
Students (Academic)Neutral or low benefitsModerate benefitsNeutral or few benefitsStrong benefits
Students (Financial)NeutralNeutral for most, but very positive for a small percentageNeutralVarying, but positive for most
ParentsNeutral or low costsNeutral or to moderate costsNeutral or low costsVarying, depending on parents’ burden of financing the child’s college education
SchoolsVarying costs or benefits, depending on contextVarying, depending on contextVarying, but usually positiveVery costly for districts, but very beneficial for states

In summary, students benefit most — academically and financially — from full-grade acceleration. Parents generally incur weak or neutral costs from their children participating in gifted programs, though there is an exception if their child skips a grade and the parent shoulders much of the burden of the child’s college education. The biggest wildcard is for schools: for enrichment, single-subject acceleration, and standalone or magnet programs, the financial costs and benefits can vary greatly. Even full-grade acceleration varies in its financial impact on government entities; for states grade skipping can save a lot of money, whereas districts lose financially from allowing grade skipping.


I hope that this post is not the last word in cost-benefit analyses of gifted programs. I am not an economist, and my analysis is very simplified. For example, I did not separate opportunity costs from marginal costs. Likewise, I did not examine the potential psychosocial benefits of gifted programs for students, nor the nonfinancial benefits that parents or schools may obtain (e.g., bragging rights to other parents, prestige for schools). There is a lot to learn at this intersection of educational psychology and policy, and I hope that this post inspires further work on this topic.


Assouline, S. G., Colangelo, N., VanTassel-Baska, J., & Lupkowski-Shoplik, A. (Eds.). (2015). A nation empowered: Evidence trumps the excuses holding back America’s brightest students (Vol. 2). Belin-Blank Center.

Bui, S. A., Craig, S. G., & Iberman, S. A. (2014). Is gifted education a bright idea? Assessing the impact of gifted and talented programs on students. American Economic Journal: Economic Policy, 6(3), 30-62. https://doi.org/10.1257/pol.6.3.30

Card, D., & Giuliano, L. (2016). Universal screening increases the representation of low-income and minority students in gifted education. Proceedings of the National Academy of Sciences, 113(48), 13678-13683. https://doi.org/10.1073/pnas.1605043113

Frisvold, D. (2015). The costs of acceleration, deconstructed. In S. G. Assouline, N. Colangelo, J. VanTassel-Baska, & M. Sharp (Eds.), A nation empowered: Evidence trumps the excuses holding back America’s brightest students (Vol. 1, pp. 60-65). Belin-Blank Center.

Gallagher, J. J. (2000). Unthinkable thoughts: Education of gifted students. Gifted Child Quarterly, 44(1), 5-12. https://doi.org/10.1177/001698620004400102

Kim, M. (2016). A meta-analysis of the effects of enrichment programs on gifted students. Gifted Child Quarterly, 60(2), 102-116. https://doi.org/10.1177/0016986216630607

Klopfenstein, K. (2010). Does the Advanced Placement program save taxpayers money? The effect of AP participation on time to college graduation. In P. M. Sadler, G. Sonnert, R. H. Tai, & K. Klopfenstein (Eds.), AP: A critical evaluation of the Advanced Placement program (pp. 189-218). Harvard Education Press.

Klugman, J. (2013). The Advanced Placement arms race and the reproduction of educational inequality. Teachers College Record, 115(5), 1-34.

McClarty, K. L. (2015). Early to rise: The effects of acceleration on occupational prestige, earnings, and satisfaction. In S. G. Assouline, N. Colangelo, J. VanTassel-Baska, & A. Lupkowski-Shoplik (Eds.), A nation empowered: Evidence trumps the excuses holding back America’s brightest students (Vol. 2, pp. 171-180). Belin-Blank Center.

Miravete, S. (in press). Should talented students skip a grade? A literature review on grade skipping. European Journal of Psychology of Education. https://doi.org/10.1007/s10212-022-00614-z

Rogers, K. B. (2007). Lessons learned about educating the gifted and talented: A synthesis of the research on educational practice. Gifted Child Quarterly, 51(4), 382-396. https://doi.org/10.1177/0016986207306324

Rogers, K. B. (2015). The academic, socialization, and psychological effects of acceleration: Research synthesis. In S. G. Assouline, N. Colangelo, J. VanTassel-Baska, & A. Lupkowski-Shoplik (Eds.), A nation empowered: Evidence trumps the excuses holding back America’s brightest students (Vol. 2, pp. 19-29). Belin-Blank Center.

Wai, J. (2015). Long-term effects of educational acceleration. In S. G. Assouline, N. Colangelo, J. VanTassel-Baska, & A. Lupkowski-Shoplik (Eds.), A nation empowered: Evidence trumps the excuses holding back America’s brightest students (Vol. 2, pp. 73-83). Belin-Blank Center.

Wai, J., Lubinski, D., Benbow, C. P., & Steiger, J. H. (2010). Accomplishment in science, technology, engineering, and mathematics (STEM) and its relation to STEM educational dose: A 25-year longitudinal study. Journal of Educational Psychology, 102(4), 860-871. https://doi.org/10.1037/a0019454

Warne, R. T. (December 27, 2016a). Publication bias currently makes an accurate estimate of the benefits of enrichment programs difficult: A postmortem of two meta-analyses using statistical power analysis. Retrieved from ERIC database. (ED572464) http://files.eric.ed.gov/fulltext/ED572464.pdf

Warne, R. T. (2016b). Five reasons to put the g back into giftedness: An argument for applying the Cattell–Horn–Carroll theory of intelligence to gifted education research and practice. Gifted Child Quarterly, 60(1), 3-15. https://doi.org/10.1177/0016986215605360

Warne, R. T. (2017a). Research on the academic benefits of the Advanced Placement program: Taking stock and looking forward. SAGE Open, 7(1), Article 2158244016682996. https://doi.org/10.1177/2158244016682996

Warne, R. T. (2017). Possible economic benefits of full-grade acceleration. Journal of School Psychology, 65, 54-68. https://doi.org/10.1016/j.jsp.2017.07.001

Warne, R. T., Larsen, R., Anderson, B., & Odasso, A. J. (2015). The impact of participation in the Advanced Placement program on students’ college admissions test scores. The Journal of Educational Research, 108(5), 400-416. https://doi.org/10.1080/00220671.2014.917253

Warne, R. T., & Liu, J. K. (2017). Income differences among grade skippers and non-grade skippers across genders in the Terman sample, 1936–1976. Learning and Instruction, 47, 1-12. https://doi.org/10.1016/j.learninstruc.2016.10.004

Warren, J. R., Hoffman, E., & Andrew, M. (2014). Patterns and trends in grade retention rates in the United States, 1995–2010. Educational Researcher, 43(9), 433-443. https://doi.org/10.3102/0013189×14563599