You can use Air Freshener to clean a dry erase board that just won't erase board. Spray the board and wipe. It also helps "recondition" old dry erase boards. Don't use this method on an ActivBoard or Smart Board in the classroom--only dry erase boards!
Woolite Foam Carpet Cleaner - Sprays out in foam stream so you can spray right on grout line. Let set several minutes, brush, wipe away. Easiest way ever to clean gross grout! I love Woolite carpet cleaner anyway.
29 Clever Organization Hacks For Elementary School Teachers