Okay! Call me old and grouchy.
In fact, I am getting old but I'm still going to recommend Strunk & White's "Elements of Style" for two reasons: 1) That's how I learned the vagaries of grammar, punctuation, usage, etc. and I've used "the little book" successfully in ESL, composition, literature and creative writing classes. 2) The major reason is that no student wants to spend--or needs to spend--hours going through interminable grammar and punctuation exercises.
Instead, use E. B. White's marvelous book to learn the fundamentals. Then, student and tutor can begin to learn how to write, edit and re-write. A far more profitable and enjoyable line of work.
I have written professionally for over forty years. Far more helpful than grammar and punctuation tests is a good ear. If something sounds wrong, it most likely is! The last thing to try to memorize are dozens of meaningless rules. Spend that precious time on developing a topic and re-writing for impact and clarity. You'll discover that by focusing your attention on the real priorities of writing, editing and re-writing your effort will pay far more dividends, far more quickly.
Frank R. - Los Angeles Tutor