This study investigated the effect of Polya's
problem-solving strategy on academic performance and self-efficacy in
thermochemistry among senior secondary school chemistry students in Funtua
Education Zone, Katsina State, Nigeria. A quasi-experimental pre-test,
post-test non-equivalent control group design was adopted. The population
comprised 4,250 Senior Secondary II (SSII) chemistry students across the zone.
A sample of 180 students was drawn using multi-stage and purposive sampling
techniques from two co-educational schools, assigned to experimental (Polya's
strategy, n = 92) and control (conventional teaching method, n = 88) groups.
Two validated instruments, the Thermochemistry Performance Test (TPT, r = 0.84)
and the Thermochemistry Self-Efficacy Questionnaire (TSEQ, α = 0.88), were used
for data collection. Data were analyzed using mean, standard deviation, and
Analysis of Covariance (ANCOVA) at the 0.05 level of significance. Findings
revealed that students taught using Polya's strategy achieved significantly
higher post-test academic performance scores than those taught conventionally,
F(1, 177) = 42.15, p < .001, partial η² = .19 (Cohen's d = 2.23). Polya's
strategy also significantly enhanced students' thermochemistry self-efficacy
beliefs, F(1, 177) = 31.44, p < .001, partial η² = .15 (Cohen's d = 2.84).
Both effect sizes are large by conventional standards, indicating that the
advantage of Polya's strategy is educationally, and not merely statistically,
meaningful. The study concludes that Polya's heuristic sequence is an effective
pedagogical framework for reducing abstract bottlenecks in chemistry
instruction and recommends its integration into mainstream science
teacher-preparation curricula