You can continue with CM’m beloved methods of copywork, dictation, oral and written narrration, living and excellent literature, poetry, Shakespeare, Plutarch, etc … all of that goes without saying.
A grammar program that might interest you is KISS. Every child starts at Level 1, but you choose their grade workbook. So level 1, grade 3 or level 1, grade 6. The grade determines not the grammar content but the literature in which the grammar is taught. So, a young student may be learning prepositions from Old Mother West Wind while your 5th grader is learning them from Tennyson. There are 4 (ish) levels (I think level three has more than one part).
KISS can be done in just a few minutes a day, maybe 10, and it’s a nice complement to the lovelies of CM’s approach.
I’m planning on KISS 3rd-6th and OMT as a review in high school. Thankfully, grammar is a finite subject so it does not need to be “taught” every year K-12.
This might help another poster here, I can’t remember her name, who wanted something to use with multiple children so everyone is using similar material, but at their respective levels.
Grammarland is another option for learning the parts of speech in a story form in maybe 4th, 5th, or 6th grade.
