Most students are used to passive learning (i.e. sitting in a classroom and having information “wash over” them). Since active learning is more work, some students may say that they don’t like it, or that the instructor is not “teaching them.”
Students may also be reluctant to participate in active learning because they do not know what they should “get out of active learning.” They may feel like active learning is a “waste of time” because what is discussed may not be on the exam.
You can inoculate the class against these reactions by:
Students are also encouraged to participate when they are responsible for some output. Before an activity, assign students roles to encourage participation and meaningful engagement (e.g. during group work, have one person record what is discussed and another person share it with the class).