Undergraduate physics majors typically begin their study of modern physics with special relativity. It is here that physics students first encounter the counterintuitive concepts of time dilation and length contraction. Unfortunately, the derivations of these results are often cloaked in several layers of analysis that render them rather mysterious and otherworldly for novice students. Here we show how a very simple thought experiment leads directly to a student-friendly derivation of time dilation and length contraction. The only assumption needed is the constancy of the speed of light.