Advanced Chemistry Kit
8 actual chemicals and all the kit required for 66 experiments - test tubes, beakers, safety gear, spirit burner, litmus paper. Very useful manual. Packaged, 45cm by 30cm. Not for beginners (or anyone under 10), as it concentrates on the acid/alkali spectrum but great for the keen young (and not-so-young) scientist .
This kit has the best accessible range, but don't worry they're 'mostly harmless'. But check the manual first before you try combinations .