I've just received a packet of posters to grace the walls in my office. They're all grammar and spelling-related.
The idea is that I can save my vocal cords by silently pointing to the appropriate poster(s). In extremis I can photograph the relevant bit and mail the snaps to the student… or colleague.
It's a shame that we have to spend so much time on basic literacy: clearly some schools are failing. It's not just pedantry - English is a stunningly flexible and subtle language, so an inability to utilise it well limits intelligent people to a horrendous degree. Get the basics right, then move on to the complex ideas you're trying to express.