UC Irvine

Mathematics and reading skills are targeted by wide-ranging educational policies in hopes that boosting academic achievement will improve adult attainments. Relying on theories of skill building, researchers and policy-makers have pursued the idea that early gains in skills will lead to the acquisition of later skills, and this skill-building trajectory should lead to adult economic success. In this dissertation, I examined this long-run academic skill acquisition process in mathematics by investigating several approaches to promoting mathematics achievement during the preschool and elementary school years. I then turned to the hypothesis that boosting academic achievement during the schooling years should lead to greater economic success in adulthood.

In the first study, I investigated whether early math learning impacted later math achievement in a sample of children recruited for participation in a preschool mathematics intervention program. To generate causal estimates of the impact of early learning on later achievement, I leveraged random assignment to the preschool mathematics program as an instrument for gains in early math skills. I found some indication that instrumented gains in early math skills affected math achievement measured 6 to 7 years later, but estimates were smaller than had been reported in previous correlational studies. These findings suggested that theories of skill building may have over predicted the long-run returns to early investments in mathematical skill development.

In the second study, I evaluated the effects of a 2-year intervention that encouraged second- and third-grade teachers to individualize instruction in mathematics. Individualized instruction is thought to help students at all achievement levels gain skills through tailoring instruction to the individual needs of each student. Results suggested that the intervention had little impact on math achievement at both grades assessed, and I found no impact of spending two consecutive years in individualized math instruction. However, teacher implementation was poor, suggesting that teachers may be resistant to programs that encourage them to differentiate instruction in mathematics.

The final study examined the link between adolescent achievement test scores and adult earnings. Although many studies have reported links between test scores and earnings (e.g.., Currie & Thomas, 2001; Murnane et al., 2000), most studies have only controlled for simple demographic characteristics (e.g., race, gender), leaving concerns that reported estimates might contain substantial bias. Using nationally representative data from the United Kingdom, I found that adolescent math and reading scores predicted adult earnings through age 50, but results were highly sensitive to the inclusion of a large set of controls (e.g., IQ, personality, parenting characteristics). Although fully-controlled estimates were still positive and significant, my results suggest that using the correlation between test scores and earnings to project educational program impacts may lead to biased predictions.

In final chapter, I discuss the implications of these findings for educational theory and policy. In particular, I suggest that theories of skill building need revision and more work is needed to understand the mechanisms that connect academic skills to important life outcomes.