I consider my grammar curriculum to be introductory, despite many or most students having been exposed to grammar in their elementary schools.
I introduce students to all 8 parts of speech, sentence errors, comma rules (as needed), and some other basic conventions of language.
Most of my lessons are bundled into a grammar unit, but I also teach mini-lessons as needed. For example, I might offer a mini-lesson on apostrophes if I notice, while grading an essay, a majority of students demonstrating difficulty in this area.
Unfortunately, during the course of a busy year filled with all sorts of topics, I can't always expose my students to the type of immersion in grammar that might dramatically and immediately affect their reading, writing, and speaking. However, I offer them a significant and meaningful introduction to terms and concepts of grammar so that, in subsequent years, they have a solid foundation for more sophisticated learning.