Science educators recommend that we use more student-active exercises, especially critical thinking exercises. This can be relatively easy to do in labs where students can design and conduct their own experiments. But it is also possible to develop more lecture-based exercises that ask students to build on scientific studies presented in their textbooks. I show a variety of types of questions based on ecological studies presented in Campbell and Reese’s Biology. Question types include suggesting follow-up questions, designing experiments, and ethically evaluating different courses of action. I also show sample responses to the questions by students in first-year and upper-level courses. Student responses show that most students are capable of the required analysis and synthesis.