Here's a grammar guide for revising some common modal verbs in one place. You can do it in class time as an activity. Students just need to put a tick in the box of each case which is appropriate for each modal. There are some cases which suit several modal verbs. Also, while doing the activity, you can ask similar modal verbs that may suit the situation described in the box. After the activity, you can place it on classroom walls as a reference point or suggest your students use it as a reference point at home.
It'll be an excellent opportunity to revise modal verbs in an upper-intermediate class. They'll have a chance to show that they know the uses of modal verbs. You can also ask for example sentences with the modal verbs which suit the case in the box. After eliciting some sentences, you'll have a good idea whether you need to revise more or less about each modal verb.