Here is a learning support on writing the compound sentence with a semicolon and no conjunction. This is a full page of text, but like everything else here, you can do with it as you wish: it is formatted in Microsoft Word.
I have a lesson plan in the works on this piece of procedural knowledge, so check back if this is something you want your students to be able to do.
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.