A magnetic accelerator is a chain reaction device. It is built in a series of stages, each containing a magnet, a spacer, and a projectile. To start the chain reaction, a steel ball is released, which accelerates towards the first stage magnet. When it strikes the magnet, its energy is transfered through the magnet and spacer into the projectile which speeds off toward the next stage. The process repeats until the last projectile leaves the end of the device. The more stages an accelerator has, and the more powerful the magnets are at each stage, the faster the ball bearing will leave the final stage. This four-stage device features powerful rare-earth magnets, steel ball bearings, and 25cm firing trough.

The trebuchet was most highly evolved catapult type weapon of its time. Built on location, it was able to hurl carved stone balls weighing up to 300lb (136 kg) at enemy fortifications and at a safe distance from enemy fire. This tabletop trebuchet kit is designed to withstand rigorous use, safely and reliably when using the included projectiles. Each piece has been accurately machined from carefully chosen lumber, and precisely drilled to allow easy assembly. The completed model measures 20.3cm(8") x 10.1cm(4") x 15.2cm(6"). A how-to section demonstrates loading and firing the completed catapult, including tips on tuning the finished kit.

Catapults have been used throughout history. Its simplest form was the onager or mangonel, where a projectile was placed in a cup or spoon on the end of a throwing arm. The arm would be powered by twisted ropes of hair or fibre. When fired, the arm would swing up and slam into a stopping block, causing the entire catapult to buck, and sending the payload on its way. This tabletop catapult draws inspiration from this design and is powered by a powerful twisted rope skien, and features a simple spoon and arm type arrangement. Each piece has been accurately machined from carefully chosen lumber, and precisely drilled to allow easy assembly. The completed model measures 20.3cm(8") x 10.1cm(4") x 15.2cm(6"). A how-to section demonstrates loading and firing the completed catapult, including tips on tuning the finished kit.

The science project catapult kit allows you to tinker with the design of a medieval siege weapon, and provides you with the information needed to analyse your results. The catapult can be changed from a wheeled, sling type trebuchet, to a bucking spoon-arm onager in minutes. Power the siege engine with a free-swinging counterweight or fixed rubber bands. Vary the counterweight mass, projectile mass, or sling length. Install the optional crash bar or let the arm swing free. Compare the results of all the different configurations, and draw your own conclusions about which design is the ultimate medieval artillery weapon.

Truss bridges have been a mainstay of civil engineering for many years. From early railroad structures to modern spans like the Bluewater Bridge in Port Huron, MI, truss bridges continue to be indispensible to our transportation network. This kit features all-wood construction. The materials have been carefully selected, accurately cut, and precisely drilled to allow easy assembly without tools or glue. The included instructions demonstrate how to build any one of six different structures using the color coded parts. The finished truss bridge measures 13" x 4" x 3.5" (33cm x 10cm x 89cm), with a structural span of 12" (30 cm).

Gourds, known as Mates in Peru, are a pumpkin like vegetable that grow to be rounded, conical or light bulb shaped with many variations.

Gourd Critterz focuses on animal designs from all over the world. Our collection includes animals typically found in Zoos, Aquariums, Marine Mammal Centers, National Parks, Natural History Museums, Nature Centers and more.

This baby giraffe is shown at rest, with legs sprawled on the ground.

This porcelain miniature kitten shows a very curious young cat looking up at something that has caught her attention.

These panda cubs are roughly 1.2"H x 1.8"L in measurement and feature an assortment of poses as the panda cub orients itself and the bamboo stick to eat.

This playful scene measures 1.8"H x 3"L and depicts a cat gone fishing for food.

This Christmas themed dolphin measures 1.5"H x 2.5" and features a holiday wreath around the dolphin and a cord to hang the ornament.

This Little Critterz turtle features a bandage across its body, having been rescued and aided in order for it to return safely into its natural habitat.

Root-Vue Farm® Refill Kit includes eight expanding soil wafers, carrot, radish & onion seeds, I.D. labels, and experiment booklet.

Children can make mass accelerating launch balls and discover the science of elastic collisions with this kit. Users can even mix and mold a supercharged planet collision accelerator that fires a small "moon" into orbit. The kit includes four graduated-size molds and instructions and materials for over six activities.
— In August 2010, Jessica Wood, buyer for Northshire Bookstore in Manchester, Vt., told TDmonthly her store sells “Approximately six (Hyperlaunchers) per month. I just got them back in, but I sold out right away."

This kit lets children grow up to nine large crystals, including "golden citrine," "emerald green" and "aquamarine blue." It includes a bag of granite stones, LED display stands, goggles and detailed instructions.
— As of September 2010, this product had 3 out of 5 stars from 2 reviewers on Amazon.com. One reviewer described the kit as "amazing," but consumers complained the crystals took too long to grow.
— In summer 2010, four of 43 retailers told TDmonthly that rocks and crystals are best selling science and nature products.

This kit is designed to teach children scientific principles while recycling common trash to create toys. Projects include a hover device and a cyclone tube. Parts and instructions are included.
— In an August 2010 survey, 12 percent of 43 retailers named Toysmith science kits a top seller in the science and nature category.
— “The Eco Science Toys from Toysmith have done pretty well … the whole line.” Jeff Oslick of The Enchanted Toy Store in Fullerton, Calif., told TDmonthly in late summer 2010.

Snap Circuits allow children to create electronic projects including AM and FM radios, digital voice recorders, burglar alarms, doorbells and more. All pieces are mounted on plastic modules and snap together with ease. This Pro version contains over 75 parts and an illustrated manual for building over 500 experiments. The set uses four AA batteries.
— In late summer 2010, six of 43 retailers named Snap Circuits a science and nature best seller.
— In August 2010, Jim and Retha Davis, owners of Kid’s Center in Tucson, Ariz., told TDmonthly their store sells “about 100 (Snap Circuits) a month.”
— In a late Summer 2012 survey, four out of 12 retailers said that Elenco was one of their best selling Science & Nature toy brands.

This small aquarium comes with "live" gravel filled with beneficial bacteria, which means that no external filter is required. Snails and African Dwarf Frogs are included, and a one-year food supply is available.

This third and final volume of the "Earth Heroes" books features the youth and careers of eight of the world’s greatest environmentalists who championed the protection of wildlife. It includes the historic and contemporary figures of William Hornaday (saved the bison from extinction), Ding Darling ("A Duck’s Best Friend"), Rachel Carson (author of Silent Spring), Roger Tory Peterson ("Inventor of the Modern Field Guide"), R.D. Lawrence ("Storyteller for Wolves"), E.O. Wilson ("Lord of the Ants"), Jane Goodall ("Champion for Chimps"), and Iain and Saba Douglas-Hamilton ("Saving the Elephants"). This highly readable volume with illustrations and photographs calls attention to the waves of influence that spread from the ideas and actions of these heroes for the Earth.
Awards: 2010 Mom's Choice Award - Gold Medal

In this second of the BLUES Go Birding series, five adorable cartoon bluebirds go on another bird watching adventure. This time they follow in the footsteps of the famed Roger Tory Peterson, and see birds on every coastline of America. Filled with both information and entertainment, the BLUES are a delightful introduction to birdwatching and the major shorebird species for children.

Which planet spins backwards? When is a star not a star? If you miss your flight to Mars, how long will you have to wait for the next one? All answers are revealed in this kit’s activity cards and fold-out solar system guide. "This deluxe kit lets you explore the solar system, planetarium and moon with the mars rover model and launch an expedition with the remote control rocket," SmartLab Toys Director of Sales and Marketing Darcy Morris told TDmonthly.

What mystery material is on a toothbrush? Where is the coldest place on Earth? Why are frogs famous for being slimy? This kit’s 12 activity cards reveal all. "This deluxe kit combines our You-Track-It Weather Lab, Indoor Outdoor Microscope and Extreme Secret Formula Lab all into one," SmartLab Toys Director of Sales and Marketing Darcy Morris told TDmonthly.

With this kit, kids can explore the science behind weather using this interactive station to track wind, rain and temperature. Five experiments take children from challenging the local weatherman to predicting the weather using crickets. "A full-on forecasting station," SmartLab Toys Director of Sales and Marketing Darcy Morris told TDmonthly.

Young readers are introduced to the alphabet and corresponding animals at the same time. Wild Animals literally jump, slither, and fly off the page in this illustrated pop-up featuring 26 creatures hidden within the pages of the book. Antelope bursts through the letter A; Leopard lurches from behind L; Giraffe reaches its long neck over G; Koala peeks from behind K; and Penguin waddles out from behind P. The book also includes accompanying playful first-person text designed for reading aloud with a young child and photographs of each animal.

Kids can explore one of the most destructive forces on earth with this kit. Children can paint and display seven different types of volcanoes and a geyse, and create eruptions up to 6' high. The kit also includes a 32-page fact booklet.