A college education is expected to improve students' critical thinking skills. Keeping students active in class--through writing activities and class discussion--has been shown to help students think critically. In this article, creative hands-on activities, which are common in engineering courses, are shown to improve students' critical thinking skills in a general education course. The activities were sandwiched between pre-writing, reflecting, and writing assignments. Improvements in critical thinking skills were evaluated by comparing student pre-writing with the final paper. Overall, carefully developed hands-on activities increased student critical thinking, especially when students wrote reflections in a journal shortly after completing an activity.