We are going to need more help with grammar.

Let’s say you tried these ideas for composition and grammar.  Based on the essay your teen just wrote after she read Five Feet Apart you have determined she needs to start over.  You need a textbook.  Our nine year old grandson, Paul, is using Easy Grammar.  I am teaching him how to diagram sentences from his book.  Lacie, a freshman, is using Warriner’s English Grammar and Composition.  Warriner’s has courses one through six.  Warriner’s First Course is for seventh grade and Sixth Course is for twelfth grade.  Teacher’s manuals are harder to find and expensive.  Instead google specific questions when you get stuck.  Easy Grammar and Warriner’s are widely available on eBay.  When your teen writes the next essay, try Grammarly.  Once you have a copy of Warriner’s you will be in position to answer about comma splices.