(Replies to yesterday's post on the datastore forthcoming, btw - thank you to all who responded! I'm swamped with email on the road and waiting for a stretch during which I can compose actual thoughtful replies.)
We got cheap 4GB ones from the local computer store, all identical - we're going to have the kids make keychains to attach to them so the sticks will be (1) personalized, (2) identifiable, and (3) bigger and therefore harder to lose.
For the "stick" part of Sugar on a Stick: are there some sticks that are better than others? Flash memory wears out over time - do some brands or types of sticks wear out faster than others, or is the cheap bulk brand from Microcenter equal to the fancy ones 1.5x the cost? How long, on average - and you'll have to define "average use" - should a deployment expect a SoaS stick to last?
My suspicion is that (1) it really doesn't matter, and (2) long enough - the only extra thing expensive sticks might get you is slightly better-looking sticks and improvements in mechanical construction (cap, cover, etc). But I do not know the manufacturing factors that affect flash life, nor whether different companies are likely to have different setups, tolerances, quality control, or so forth. (Come to think of it, this might be a cool "How Stuff Is Made" video if there isn't one already.) I also guess that the mean time to failure will be greater than the mean time to kid-losing-stick. (It happens. This is why backups are important.) But those are only unsubstantiated guesses.
A good lazy Sunday project, or even a "I have to write a paper for my science class" paper, if you're a student, would be to get a
number of sacrificial thumbdrives (multiple of each type, all brand-new) and do http://www.bress.net/blog/archives/114-How-Long-Does-a-Flash-Drive-Last.html on each.