Teachers usually set up the problems and ask students to provide solutions. Two alternatives to this standard procedure will give students practice with both framing and solving problems:
After you introduce a new concept in your course, ask students to write out a theoretical or practical problem that the concept might help to solve. Students can exchange these problems and write out solutions, thus ensuring that they understand the concept clearly and fully.
Ask students to write out problem statements before they come to your office hours for conference. (Or you might suggest that they use e mail to send you these problem statements in lieu of a face-to-face conference.) Students are likely to frame such a problem more concretely than they might otherwise do in preparing for a conference, and the resulting conference (or e-mail exchange) is likely to be more productive for both student and teacher.
Another version of this exercise is to have students write a problem statement that is passed on to another student whose job it is to answer it. Such peer answers are especially useful in large classes.