Physics faculty alert: It's very small, but teaches a powerful lesson, this little diamagnetic-properties demo kit. You get (4) plated magnets, each 1/4" square x 3/32", and (2) 1/4" square pieces of graphite to float above them. The graphite may have slight chips along the edge but that won't affect the effect. Includes instructions/fact sheet.

Based on drawings from Da Vinci's Codex Atlanticus, this Pathfinders catapult kit uses a pair of bent wooden arms as springs to launch clay balls (included) over (4) meters at enemy fortifications (not included, go make your own enemies). The assembled model will be approx 9" tall on a 10" x 7-1/4" base. Made from pre-cut, untreated wood from sustainable forests, and built with pegs for added strength and verisimilitude. A 2013 Creative Child Magazine Top Toy of the Year Winner and a great resource for STEM activities. For ages 12 and up.

The Tumbling Robot Experiment is relatively easy to assemble and has sensors in his (her?) belly, back and legs so he (it?) can fall and get up again, like some of us humans. At 8" tall, in between tumbles, it's a manic, sliding, chomping, swinging thingy, like a droid cookie monster in a Pilates class. You put a pair of "AA"s in his feet. Ages 8+.

Everything you need to build a little DC motor is included in this kit (except sandpaper, screwdriver, scissors and, of course, an AA battery). The instructions are simple and explain the theory as well as assembly. Fun and educational for ages 12 and up.

We spit on plastic. And so will you when you see these laser-cut bright steel models from Fascinations®. Snap-together pieces. The models are small, but worthy of permanent display, and designed for the grown-ups to assemble and display, rather than the kids to play with. You pick the Metal Marvels™ 3-1/2” long x 2-3/4” wide space shuttle Atlantis. (They aren’t making any more big shuttles, Pilgrim.) Or the 4-1/2” tall x 1-3/4” wide at the base MetalWorks™ Eiffel Tower. Ages 14 up.

And teach a kid (8 and up) the basics of solar power. This excellent educational kit from Elenco comes with (9) 0.5VDC solar cells pre-wired in sets of (3) and mounted in a 5" x 4" x 7/16" black-plastic frame with screw terminals on the bottom. The kit includes a 1.5VDC motor with leads and a mount, a fan blade and (4) plastic discs from 5/8" dia to 2" dia for mounting on the motor shaft, a 1.5V incandescent bulb with leads, a sound module with leads, and graphic cards to mount on the discs. Comes with a 14-page instruction/experiment booklet, including info on increasing voltage and amperage, powering battery charges, radios, games, etc. Lots of science project potential. "Heuristic as all get-out," Jarvis said when he saw it. Ages 8+.

Make like a miniature Martin Scorsese and create your own (stop-action) movie. Best part? The actors are all Lego® people, who work for free. You’ll get (36) assorted Lego® pieces, including mix-and-match characters and props. Includes a 78-page guide with advice for making credits, sound effects, lighting, camera techniques, set design, backdrops, storyboards and a bunch more. If Hitchcock had had this kit, Janet Leigh might have survived the shower scene. For ages 8+.

From Fascinations®, these small model kits are made from intricately laser-cut polished steel. Punch the pieces out from the 4-1/4" square sheet and put them together with the tiny tabs. You pick the dragonfly, with a 4-1/2" wingspan or the Black Pearl pirate ship, approx 3-1/2" long. For ages 14+, because they take plenty of small motor skills.

For the steady-handed model-maker. These mini-models from Metal Earth® are demanding and beautiful. Use a tweezers to punch out the little pieces from the laser-cut shiny steel sheets, and assemble them using the tabs and slots--no glue, no screws. You pick the Hubble Telescope (3” x 2” x 2-1/2”), the U.S.S. Arizona (5-3/4” long) or the 1908 Ford Model T (3-1/2” x 1-7/8” x 1-3/4”). All include instructions, which you’ll need. For ages 14+.

This 50-page book has the materials and plans for making a total of (11) Harry Potter fliers, including the above-mentioned plus the Chinese Fireball, Harry and Draco Quidditch, the Golden Snitch, Norbert the Norwegian Ridgeback, Hedwig the Snowy Owl, Fawkes the Phoenix and Gringotts Dragon. Includes lavish illustrations and a flight log.