Limited structured exposure to pharmaceutical literacy among high school students may reduce their understanding of dosage forms, prescription interpretation, and safe medication use in daily life. This community engagement activity aimed to improve eleventh-grade students’ knowledge and practical skills in preparing divided powders and capsules through an interactive prescription-based workshop. The activity was conducted offline at the Faculty of Medicine and Health Sciences, Atma Jaya Catholic University of Indonesia, involving 29 eleventh-grade students from a private high school in Tangerang, Indonesia. The program consisted of material delivery, prescription simulation, hands-on practice, discussion, and evaluation using pre-test and post-test instruments. Practical skills were evaluated through facilitator observation of key performance indicators, including powder mixing, visual dose division, capsule filling, capsule closing, labeling, and work neatness. The results showed that students’ knowledge scores increased from 75.17 ± 12.43 to 93.79 ± 9.79, representing a 24.77% improvement. The Wilcoxon signed-rank test confirmed a significant difference between pre- and post-intervention scores (Z = -4.327; p < 0.001). Most practical skill indicators were also achieved well, with observation results ranging from 80% to 100% across the assessed indicators. This activity strengthened students’ pharmaceutical literacy and can serve as a practical school-based model for early pharmacy education.