This kit is packed with materials kids need to complete 25 light activities—from making a kaleidoscope to constructing a pinhole camera! Plus, the kit includes a highly visual, step-by-step 40-page book that encourages independent use…and access to an online science portal with interactive activities, games, links and more. It’s scientific learning with a touch of whimsy! Kit comes with tons of materials to complete the activities, including magnifying glasses, alligator leads, mirrors and more. Book measures 10". Requires one 1.5-volt button cell battery (not included).