Okay, I simply didn't know where to put this. Over the past few years, I've been getting catalogs of science toys. I simply don't have space to keep all those catalogs, so I'm putting my list here so I don't have to.
Although I've labeled this with the word "toy," much of the equipment that is sold is not really toys; that's just what my wife calls them....
Science Equipment Suppliers
Accent Science - Lots of general science equipment with gadgets to equip your school (or home!) lab. Located in Buffalo, NY.
Learning Technologies - This company sells Project Astro materials as well as other astronomy educational materials (and games!). Located in Somerville, MA (hey! I used to live there).
Edmund's Scientifics - Doesn't everyone know about this one? Their have more items that really do qualify as toys in the usual sense, but plenty of the little projects qualify as science lessons. An who doesn't want a table-top trebuchet kit? Located in New Jersey(?).
Okay, these are not really "science" suppliers, but sometimes finding motivational thinks like posters and stickers is hard.
Trend Enterprises - The make/distribute sparkle planet stickers. Elementary kids love stickers and these were very popular with the 4th and 5th grade astronomy club kids. The local store had them, but had trouble getting more in stock, so I eventually ordered online (same price, so if you only need a few, try to buy local).
Teacher Storehouse - I don't know that they are really any better than anyone else, but I did like the astronomy posters I found there, particularly the one on the moon phases. I don't like their Solar System chart though; the planets are not to the same relative scale. I find it much more useful to select one where the planets are imaged at the same relative scale.