Here is a learning support on the use of parentheses. I’ve published quite a few of these recently; they have all been excerpted from Paul Brians’ book Common Errors in English Usage, which he has posted at the Washington State University website.
This document is really only a paragraph of text, so there is a big blank field on the page. In other words, plenty of room to write some exercises for students to practice using parentheses correctly. Because it is a Microsoft Word document, you have plenty of ways to convert it to your favorite word processor and adapt it for the needs of your classroom.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.