Math manipulatives can be full of tiny pieces. I bought a small 3 drawer rolling cart from Target to house my math supplies. One drawer is for games and flashcards. One drawer is for counters. One drawer is for other manipulatives like clocks, snap cubes, fraction tiles, and place value blocks. I bought dried beans and pasta to use as counters. I dumped those into ziplock bags. Other counters I have stored in little plastic food containers. Nothing is just dumped into the drawers loose. If I need 5 clocks for my lesson, I want to be able to pull open the drawer and get all the clocks in less than 10 seconds. I don't want to dig around in the drawer finding each clock. Students can also easily find what they need this way as well. If you number the amount of clocks you have on the outside of the bag, you can quickly see if any are missing.