Two levels of homework

As described in the syllabus, this is a problem-solving course. That means that homework is almost always a problem-solving activity.

Problem-solving should be fun and challenging. In order to help ensure that all students have an appropriate level of challenge on the homework, we offer two "levels" of assignments each night: the regular level and the challenge level.

Students get to choose their level each night.  They should choose a level of homework that makes problem-solving fun: challenging enough to be interesting, but not so challenging as to be impossible.