Problem-Solving Skills in Integral Calculus: A Retrospective Causal-Comparative Analysis of Pre- and Post-Exposure to The Organic Chemistry Tutor

This retrospective causal‑comparative study determines whether a significant difference exists in the Integral Calculus problem‑solving skills of students after exposure to video lectures by The Organic Chemistry Tutor, compared with their proficiency level prior to exposure. This widely accessed educational creator was selected because of its clear, step‑by‑step instructional style, free availability, and demonstrated effectiveness in simplifying complex mathematical and scientific concepts, qualities that address common barriers in teaching technical calculus topics. The participants comprised 22 second‑year Bachelor of Secondary Education major in Mathematics students enrolled at the Polytechnic College of the City of Meycauayan-Annex during the Academic Year 2025‑2026. Adopting a quantitative one‑group pretest-posttest design, the study used a 15‑item test on integration by parts. Data were analyzed using mean and standard deviation, paired‑samples t‑test, and Cohen’s d for effect size. Results show a substantial improvement in mean scores from 5.32 (Beginning proficiency level) in the pretest to 10.50 (Proficient level) in the posttest. The difference was statistically significant (t = -17.733, p < .001), leading to the rejection of the null hypothesis, with a very large effect size (d = 3.79). Findings suggest that instructional videos such as those by The Organic Chemistry Tutor effectively enhance problem‑solving skills in Integral Calculus. It is recommended that faculty integrate such resources into instruction and that the institution strengthen ICT‑enabled learning. Keywords: Integral Calculus, Problem‑Solving Skills, Instructional Video Lectures, Integration by Parts, Pretest-Posttest Design, Paired‑Samples t‑Test, ICT‑Based Learning