Background: Integrating public health into science courses helps students grasp the links between health recommendations and scientific principles. During COVID-19, a team of 19 educators, scientists and clinicians designed 25 science inquiry lessons to enhance disease knowledge and prevention strategies among school-aged children. The efficacy of two lessons was evaluated. Design: Pre-/post-evaluation; both quantitative and qualitative data were collected. Setting: Teachers (24 elementary and 26 high school) and their students (562 elementary, 8–9 years old; 1,271 high school, 14–15 years old) participated from schools in Houston, TX, USA. Method: Lessons were delivered in Spring 2021. Teachers completed evaluation surveys using Likert-type and open-ended items. Students completed pre- and post-assessments of COVID-19 knowledge, attitudes towards science and confidence in their knowledge of COVID-19 and vaccine science. Results: Over 80% of teachers agreed that they would use the lessons again and felt more confident in their abilities to teach about COVID-19 after using the lessons. Teachers reported students’ heightened interest in health professions and discussing the presented topics. High school students gained basic recall knowledge, but there was little change on items related to in-depth science concepts or attitudes. Elementary students demonstrated gains on items related to the scientific rationale underlying public health recommendations and confidence in their abilities to protect themselves from COVID-19. Conclusion: The integration of health information into science teaching helps learners understand the science behind public health recommendations and increases teachers’ preparedness and comfort levels with these topics. Even short-term supplementary lessons can have a positive impact on knowledge and attitudes. Effects were particularly positive with elementary students, who should be included in future public health education efforts. Partnerships between schools and health organisations are vital for the rapid development and integration of lessons that are accurate and informative. The lessons evaluated in this paper are freely available online.