The Making Pre-K Count and High 5s studies test two math programs to examine whether it is possible to improve children's early math abilities, and whether improvements in this "linchpin" outcome lead to impacts on children's other short- and longer-term outcomes. The current analysis examines the cumulative effects of both programs on children's math, language, and executive function skills in kindergarten. The Making Pre-K Count program entailed a comprehensive redesign of both the content and teaching of math in the prekindergarten (pre-K) classroom, and the High 5s program provided a second year of math enrichment for a subgroup of children who received Making Pre-K Count in preschool. High 5s was designed to build on children's pre-K experience using small-group math clubs -- in which a trained facilitator works with three to four children on fun math activities three times a week outside the classroom -- to supplement regular kindergarten instruction. (author abstract)