At school we're preparing for some hardcore end of year cleaning. I know that our operations manager was concerned specifically about removing permanent marker from desks and tables. As she put it, the heavy duty chemical cleaner we have "is like acid. We're almost guaranteed to have an accident if the kids or teachers are using the stuff!" Being the good citizen I am, I quickly jumped into action to prevent such a catastrophe.
Earlier this year, I learned about a ridiculously simple method to remove permanent marker from most surfaces:
Write over the permanent marker with an Expo or other dry erase marker!
I did not believe it either when I heard about it, but it works. What happens is that the dry erase/non-permanent Expo ink mixes with the permanent marker and sort of turns it into dry erase ink. It's science! After covering the affected area, the same Expo cleaning fluid you use on the whiteboard can be used to clean it off.
Really stubborn marks might take a "coat" or two to be completely removed (as one particularly annoying message scrawled into a table in my room did) but it will work. I don't know the source of this idea, but I'm pretty sure I read it on one of the wonderful blogs I frequent (see my blogroll if you're up for investigating).
Another end of year nuisance I am used to dealing with is sticky, gunky tape residue left over from packing or duct tape. I always had a mess to clean up when I removed the numbers I had taped to my student desks with packing tape in years past. Water or regular cleaning solutions don't really help; using some kind of scraper will damage the surface. The best way to get it off is also really simple.
You can remove it by taking a new piece of tape, pushing it down onto the gunky area, and pulling. Then repeat many, many times. It is admittedly a time-consuming and laborious process, but it removes the tape residue without damaging the surface. It would be a great thing to have some students do when they're ready to help out! (Side note: This also works for removing pesky labels and stickers from books, CDs and DVDs).
As with the first idea, I'm not sure where I learned this, but thank you to whoever taught me. I think I took it for granted that everybody knew these tips until I shared them at school and received a lot of shocked or surprised reactions. I hope you find them as helpful as I have.
Please share your best cleaning secrets in the comments!