Zivko the Robot. Our best selling STEM kit ever! Just call her (or him--it’s unclear and we don’t like to ask) “Zivko” because “the Robot” is her last name. Using just a screwdriver and side cutters, you build Zivko from this 107-piece S.T.E.M. kit. Set the mode for “Follow Me” or “Explore,” and Zivko will, yes, track you, or evade obstacles, respectively, via an infrared sensor and micro-controller programming. Interactive LEDs and sounds abound. Measures approx 5" x 5-1/2" x 6-1/2" when assembled with all (6) legs. You add (4) “AA”s for power, which is the least you can do for someone this cute. Ages 10+.

Pop one of these roughly 1-1/4" dia stones into the toe of a sock, smash it with a hammer, and be the first person ever to see your real-as-Nature-makes-it geode!! Ninety percent of them have the familiar beautiful white crystals inside. Formed by volcanic action, they are found all over the world, but ours are from Mexico. There is no way to tell from the outside if they have crystal centers, but we will send you two just to raise your odds, and we haven't had a dud yet in our stores!! Much much more fun and satisfaction than buying one already cracked.

It doesn't get much cooler in the robotic-arm-kit game. The assembled STEM educational arm is 15" tall x 9" long x approx 3-1/2" wide. It's 2-pronged hand opens to 1-3/4", lifts up to 3.5 oz (100g), swings 120 degrees at the wrist, pivots 300 degrees at the elbow, and sits on a base that swings 180 degrees up and down and rotates 270 degrees, like, well, an arm. Controlled by (5) 2-axis joy-sticks and powered by (4) D-Cell batteries that you provide. Includes a hand-mounted search light and over-torque and gear-breakage alarms, which is more than your arm has. Requires a diagonal cutter and Philips screwdriver for assembly of its 200+ pieces and is made for ages 12 and up.

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.

Just the one, actually, but it’s been sliced in half so the pair is perfectly symmetrical and mighty pretty. Although ammonites have been extinct for 65,000,000 years, we’ve got their approx 1” dia fossils for you. Our each is a book-matched pair of polished ammonites fossils of a single critter halved and polished to a bright symmetrical shininess. The colors vary from light tan to dark brown and we’ll pick because we have impeccable ammonitical color-shade taste. And yes, they’re just screaming to become cuff-links or earrings.

Yes, we have The Amazing Live Sea Monkey® aquarium kit, just like the ones from the comic books. The (9) piece ocean zoo includes brine shrimp eggs, growth food, water purifier, plus an official plastic feeding spoon, 32-page handbook, life insurance policy, growth guarantee, and the plastic aquarium with built-in magnifiers for viewing your little friends, and a vented cover. Great gift for those budding young marine biologists. Ages 6+.

These pretty, and pretty small, polished semiprecious stones include sodalite, tiger eye, quartz crystal, aventurine, amethyst, red jasper, fluorite, and rose quartz, plus a bonus assortment. You’ll get approx 1/2 oz of each in small corked bottles, 7/8” dia x 1-1/2” tall. The semiprecious pebbles are roughly 1/8” to 3/8” long.

These (7) small gemstones--quartz crystal, amethyst, tiger’s eye, sodalite, aventurine, orange calcite and jasper--are approx 1/2” to 1” and will serve as either geologic specimens, jewelry-making supplies, or help in restoring your harmonious flow of energy depending on how you roll and what you’re into.

Could be a new line of cologne, but in fact, it’s a clever kinetic action demo kit called Wave Wires® with magnets marked for polarity, and mounted on (4) 8-1/2” long wires attached to a 4-1/4” square steel base. Includes a dozen 1/2” dia steel disc weights, an acrylic ring and an 8-page activity booklet. The attraction/repulsion magnetic properties cause the magnets to swing on top of the wires like old-time circus acrobats. Ages 8-14. Really cool, if we don’t say so ourselves.

Geology for those with short attention spans? The original Magic Rocks®, of course! Mix the solution in a jar of water, drop in the pebbles, and watch them grow into a forest of multi-color stalagmites. Growth starts in 10 minutes, is impressive in 30 minutes, and complete (up to 4" tall) in 2 hours. Extra credit if you can make it grow stalactites by gluing the pebbles to the bottom of a jar, then pouring the solution in and turning it upside down. Who knows? Maybe it will work. Comes with a set of marine decals to decorate the jar. Definitely not for use with living fish. For ages 10 and up.

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.

This is an excellent starter kit for learning the rudiments of Chinese brush painting. Includes a lavishly illustrated 47-page instruction booklet, an 11-1/8" x 8-1/8" pad with (36) practice sheets and a few sheets of xuan, the vellum-like paper that brush-painting artists use, plus 5ml tubes of Chinese watercolors in white, indigo, burnt sienna, carmine and gamboge, a saffron color. Also includes (2) brushes, an ink stone and ink stick, all in a nice boxed set.

Simple, yet clever 1" dia. by 3" long plastic device to demonstrate the vortex effect of a tornado. Partially fill with water one of the two half-gallon size plastic soda bottles which you supply. Screw the bottles into opposite ends of the tube which we supply. Tip so the full bottle is on top and give it a circular starting whirl. Presto! You have a vortex. Call it a tornado if you're a meteorologist, a Charybdis if you're a classicist, or a whirlpool if you're into oceanography. Lots of fun and a fine opportunity to attempt to explain the effects of the earth's rotation on water draining out of a bathtub. The phenomena are related we're told, but good luck!!

with our best selling electronics kit. Build 100 or more electronic projects from a Reflection Detector to a Simple Salt Water Alarm with Snap Circuits Jr. The Elenco kit, a Dr. Toy Winner, has a grid base and a selection of conductors, resistors, switches, integrated circuits and more, for a total of (30) color-coded snap-in parts. For ages 8 to 108, the easy-to-use components and well-designed instruction manual make this a perfect way to spend some quality time with a bright young child! AWARDS: The National Parenting Center-Seal of Approval, Dr. Toy 100 Best Children's Products, Dr Toy Best Educational Products. Ages 8+. See our full line of Elenco Snap Circuits here!

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. For ages 7+.

Crystals are for pointing toward you or away from you, depending on what you believe or want, or for polishing, or just for looking at. You get a 3-pack of quartz point crystals, approx 1" to 2-1/2" long, ready for psychic healing, jewelry, or plain old-fashioned lapidarian fascination. Your hunks of point crystal might have an actual point, might not: nature's like that.

if you want to sound like a steam engine, and who among us doesn't? This Velleman® steam-engine sound generator kit comes with circuit board, components, battery connectors, speaker and instruction sheet. You add solder, a soldering iron and a 9V battery. Volume and (implied) speed are adjustable and there's a horn button, so it'll go both choo-choo and whoo-whoo. Great for train hobbyists or people bored with their doorbell. Ages 10+.

When you peer through your magnifying glass at this specimen, or focus your microscope on it, even at the lower magnifications which work best, you're looking at one big bug. Make that (4) big bugs. The insects are real, encased in clear acrylic blocks 1-3/4" x 1-1/4" x up to 11/16" thick, and ready for inspection. Set 1 includes a scorpion, giant ant, wasp and a flower bug. Set 2 is a cricket, locust, yellow leaf beetle, and crab. No, not a crab louse or a crab spider, but definitely a crab ugly.