Academic vocabulary, verbal reasoning, nonverbal reasoning, and working memory directly predict sixth-grade geometric and fraction skills¶

Claim · All claims
Evidence · 1 study · associational r2 · q3
Currency · newest study 2025 · checked against its sources 2026-10-23 (automated, 1 of 1 entry) · not reviewed by a person

Subclaims¶

q3 i? Academic vocabulary, verbal reasoning, nonverbal reasoning and working memory, measured in grade 4, had significant direct effects on both sixth-grade geometric and fraction skills over and above arithmetic skills, in a predictive (not causal) mediation model. → Kleemans 2025

Evidence¶

Kleemans 2025¶

Kleemans, T., Vissers, C. T. W. M., & Segers, E. (2025). Linguistic precursors of sixth-grade geometric and fraction skills in children with and without Developmental Language Disorder. Learning and Instruction, 95, 102019. https://doi.org/10.1016/j.learninstruc.2024.102019

q3 · i? · associational · r2

Longitudinal study of 46 children with Developmental Language Disorder and 122 typically developing peers, with predictors measured in grade 4 and geometric and fraction skills in grade 6. Two mediation analyses (geometric and fraction skills as dependent variables, arithmetic as mediator, seven predictors, 5000 bootstraps, controlling for age, SES, sex and group) found significant direct effects of arithmetic skills, academic vocabulary, verbal reasoning, nonverbal reasoning and working memory on both outcomes, consistent with the advanced linguistic skills framework. The standardised path coefficients appear only in the article's Figure 1, not in its text; the full models explain R² = .66 of geometric and .62 of fraction skills. These are predictive associations and cannot show cause.

"Regarding geometric skills, the results indicated significant direct effects of arithmetic skills, academic vocabulary, verbal reasoning, nonverbal reasoning, and working memory."

"For fraction skills, significant direct effects were observed for arithmetic skills, academic vocabulary, verbal reasoning, nonverbal reasoning, and working memory."

Discussion¶

Learner Variables¶

• Geometric Reasoning — predictor: learners who differ on it differ in outcomes
• Vocabulary — predictor: learners who differ on it differ in outcomes

Related Claims¶

• Academic vocabulary is directly related to fifth-grade geometric skills over and above arithmetic skills — a narrower finding that bears on this claim
• Verbal reasoning is directly related to fifth-grade fraction skills over and above arithmetic skills — a narrower finding that bears on this claim
• Basic linguistic skills and working memory are indirectly related to fifth-grade geometric skills via arithmetic skills — related
• Basic linguistic skills and working memory are indirectly related to fifth-grade fraction skills via arithmetic skills — related
• Phonological skills were not significantly correlated with fraction skills, and verbal reasoning was not significantly correlated with arithmetic skills — related
• Phonological skills and naming speed indirectly predict sixth-grade geometric and fraction skills via arithmetic skills in both DLD and TD children — related
• Children with DLD show significantly more weaknesses and fewer strengths across linguistic and cognitive precursors than TD peers, except in verbal reasoning and arithmetic — related
• A strength in verbal reasoning partly compensates for geometry and fraction delays in children with DLD at the individual level — related