Failures to provide adequate feedback should be reported to your course instructor. Prompt arrival at the session. Students should arrive on tome at the session. When students do not show up, the researcher's time is wasted. Often researchers lose an hour or more every time a subject fails to show up.
Many instructors penalize students for failure to show up at an experiment.
Attention to feedback. Making participation genuinely educational is an obligation of students as well as researchers. Feedback is more likely to be interesting if students pay close attention to the experimenter's explanation and ask a few probing questions.