This multi-bot solar kit includes a 1.5V solar cell, a small DC motor and gearbox and a boatload of parts that will let you make (14) different solar-powered projects including: a turtle-bot; walker bot; quadru bot; wheel bot; boat bot; beetle bot; dog bot; auto bot; carb bot; slither bot; roly poly bot; surf bot; and, you should pardon the pun, the row bot. No, really--there's a row bot. Projects come in (2) levels of difficulty and include an 81pp graphic manual. You'll need a hobby knife or a pair of side-cutters, and sunlight. Most projects will be approx 5" tall when assembled.

Do your kids think the whole world snaps together? Time to get them the Steel Works, a classic steel construction set from Schylling not unlike those erecting sets of yore. Has more than (300) pieces, including beams, plates, angles, nuts, bolts, washers and more, along with instructions for making an airplane, helicopter, dump truck, satellite truck, fire truck, forklift, claw truck, gyrocopter, bulldozer and backhoe. Includes wrenches and a hex key. Models have mechanical actions triggered by wheel movement. Parts are interchangeable with any other Schylling Steel Works kit. For ages 8+.

Lego® goes crazy with this 100+ piece kit with everything you need to build (16) different contraptions (be pretty stupid if they made 16 of the same contraption) for your amusement. In the mix are gears, pulleys, belts and axles, which you could turn into a rocket racer, Lego® launcher, donkey cart or scissor grabber, among other things. Includes a 50-page spiral-bound graphically illustrated instruction booklet. And, yes, adding Lego® pieces of your own just ramps up the fun.

Right after you build your own working medieval catapult or trebuchet. All you’ll need is glue, scissors and a steady hand (plus a small bag of marbles or rocks or something as a counterweight for the trebuchet) to construct these wooden, Canadian-made siege engine kits. The catapult stands 6” tall x 5” wide x 10” long and will toss assorted stuff 15 feet or farther, depending upon the stuff. The finished trebuchet will be 26” long x 18” wide x 24” tall and will propel small objects (meatballs?) 20 feet or more. Both include detailed instructions and are great resources for STEM activities. Note: Please don’t propel small mammals, and please don’t put anyone’s eye out.

Nice little pulley unit kit includes (1) pulley each at 50, 30, 25 and 20mm and (3) pulleys at 11mm, plus myriad bushings, a 3VDC motor, (2) belts and a belt guide, base, mounts and assorted hardware. Includes graphic assembly instructions, plus a couple of rudimentary drawings with suggested projects. It's a mechanical science project waiting for a home.

In the mood for a little light levitation? Try this magnet-based kit from KidzLabs® and make a pencil float in mid-air or tell your fortune, all through the captivating power of magnets. You can even build a mag-lev robot, and who doesn't want one of those? The (7) projects are based on the (7) plastic-coated, 1-5/16" dia bored disc magnets and assorted other parts. Projects include anti-gravity sculpture, floating spinner, magnetic compass, spring and weight scale, propelling machine and a mag-lev transporter.

You're in for weeks and months of fun creating Rube Goldberg-like versions of the new VorteX 3.0, a Techno Gears Marble Mania machine. You get over (300+) colorful pieces including baseplates, 3-D connectors, channels, tubes, gears, marble twister and a marble funnel to create intricate tracks to move marbles around, down, over and through the maze. Includes a battery-operated 2-foot tall marble launcher that makes the whole thing automatic so you can sit back and watch your creation run by itself.  A STEM kit that challenges problem solving skills and expands knowledge of mechanics and engineering. You add (3) "AA" batteries and a capacity for twisted thinking.

Who woodn’t, really? In a world of plastics, it’s hard to beat a model fashioned from pieces of dead trees. You pick from our assortment of pre-cut unfinished wood models made for ages 8+, and all you add is wood glue, paint, sandpaper and simple hand tools: the 12-piece drag racer will measure 6-3/4” long x 2” tall; the 35-piece steam engine will measure 7-3/8” long x 4-3/8” tall; and the 46-piece stage coach will be 8-7/8” long x 5-7/8” tall. (Sorry, no horses.)

From Metal Earth®, the people who make shiny metal 3D models, now comes the Doctor Who metal models. All punch-outs with no glue or soldering required. You pick: the Golden Dalek, at 2-1/4” x 3” x 1-1/4”; or the Blue Tardis model at 1-5/8” square x 3-1/4” tall. And if you don’t know what a Dalek or Tardis  is, you shouldn’t even be reading this. These are challenging models, so rated for all ages over 14.

Make a whole bunch of fun and instructive Lego® machines/chain reaction models like marble runs and mousetraps involving ramps, buckets, funnels balances and much more. Comes with (33) Lego® elements, (6) Lego® balls, a dozen paper props, and a 78-page instruction booklet for (10) machines. You add a few common household items. Includes suggestions for more complicated devices if you have your own Lego® pieces, and if you don't, what are you waiting for? ! WARNING: CHOKING HAZARD–Small Parts. Not for children under 3 yrs.