I love all of these ideas for a classroom. There are bracelets to keep track of groups, paint stirrers to separate books and just basically anything to help out in the classroom. As a plus, these hacks aren't even that expensive to make happen.
Schoolgirl Style: Organize your classroom with an area designated for supplies, parent communication, notes, and all of the overwhelming paperwork that tends to accumulate on a teacher's desk. Used CTP's Lots of Dots Black Border