This SmockTip provides a simple solution. Save the cardboard drink trays that you get from a fast food drive-thru. Chances are that you also have some old paint cups laying around that fit perfectly into each drink space.
I use these recycled supply caddies in multiple ways. I often set them up with a different supply in each cup space, whatever my students happen to need that day, and put the drink trays directly on student tables. This is very handy on days when I have back-to-back classes and sections of each grade level at various times throughout the day, because I can set aside the supply caddies and bring them back out when needed later on.
I also use the trays to store cups of supplies on my classroom shelves. When I am prepping for a class and each table group needs scissors, I simply pick up the drink tray and walk around the room delivering a cup of supplies to each table like a waitress. If I only had roller skates like the waitresses at the drive-ins of my childhood, imagine how efficient I could be!