Challenge questions are posted on the classroom chalkboard. Generally, a new question is posted every Tuesday.
The object of the challenge questions is to help students recognize the applicability of the material that we are discussing in class. The information needed to answer the challenge question will be presented in class sometime during the week. These questions probably can't be answered by students at the beginning of the week but they should be able to answer the questions by the end of the week.
Answering the challenge question is a required assignment. Answers should be submitted at the beginning of each week. Because the challenge questions are related to the material currently being covered in class, late answers will not normally be accepted.