A simple way to do that is to write your problems down somewhere where they are seen often, with a simple command at the top like: Solve these: or a question

A simple way to do that is to write your problems down somewhere where they are seen often, with a simple command at the top like: Solve these: or a question to kick start this like: What is the solution to these problems: You'll quickly reach the point where you are ignoring what is written, but the subtle visual reminder will keep a small portion of your mind churning away at them.