An appreciation of genetic principles depends upon understanding the individual curiosity that sparked particular investigations, the creativity involved in imagining alternative outcomes and designing experiments to eliminate these outcomes, and the clarity of thought necessary to convince one's scientific peers of the validity of the conclusions. At large research universities, students usually begin their study of genetics in large lecture classes. It is widely assumed that the lecture format, coupled with the pressures to be certain that students become familiar with the principal conclusions of genetics investigations, constrains most if not all departures from the formats textbooks used to explain these conclusions. Here I present several examples of mechanisms to introduce meaningful student inquiry in an introductory genetics course and to evaluate student creative effort. Most of the examples involve altered student preparation prior to class and additional in-class activities, while a few depend upon a smaller recitation section, which accompanies the course from which the examples have been drawn. I conclude that large introductory classes are suitable venues to teach students how to identify scientific claims, determine the evidence that is essential to eliminate alternative conclusions, and convince their peers of the validity of their arguments.