I made a video about comma splices for this worksheet. You can use this worksheet after you teach about comma splices. I didn't teach about the semi-colon, so this is not an option in the answer key. The three methods of fixing are: making two sentences, adding a coordinating conjunction, or adding a subordinating conjunction. I hope this can be helpful in your teaching. If you use this and adapt, please also share alike. :)
donaldbcampbell