A set of 5 open-ended problems (one for each day of the week) applying number theory and modular arithmetic. Modeled after those types of open-ended questions that appear on state standardized graduation tests. Comes with answer keys and a 4-point scoring rubric that's applicable to all 5 problems in the set. Designed as a Power Point that can be presented interactively. Can be used as a "do now" bell-ringer, anticipatory set, closure activity, extra-credit assignment or as a main lesson in and of itself. By Scott Cianci.