My clorox pen stays with my scrapbook stuff also. LOL!!!
bskts4bj, I would just make sure that you use a gel instead of liquid. The liquid will work but it's so runny and easier to get places you didn't really want it. The gel stays on the stamp easier. Also the larger foam stamps are easier to do on clothing when bleaching. You can use rubber stamps if they are large patterns. Hope that makes sense. The bleach does stay better on foam.
Also make sure wherever you do it it's well ventilated. It gets rough if you have been working with it for to long.
Hope they have fun!!!