We just learned that. You’d think we’d have known. Now we do. They’re sort of like round dreidels, with a hollowed-out middle around the stem, which causes them to turn themselves upside down while they’re spinning. Great lesson in center-of-mass instruction for physics teachers. Includes an explanatory booklet with activities and discussion topics. You’ll get (3) wooden tops at 7/8”, 1-1/4” and 1-1/2” dia.

An easy way to light up the kids' eyes! Teach them to wire a simple circuit with our basic components.

• The knife switches are mounted on a plastic bases.
• The miniature plastic socket holds a standard flashlight bulb with a 14 mm dia screw base.
• We pack 6 volt and 3 volt round bulbs, or 1.5 volt bell-shaped bulbs, (5) to a package.(Bulbs are rated slightly higher to prevent them from burning out.)
• Hook up the black plastic and metal 2" x 4-1/4" telegraph key with brass contacts and (2) terminal posts with nuts.
• Our blue-plastic holder for (1) "D" battery has a small tab at each end to hook a lead to, and a 1/8" square mounting hole at each corner.
• You add the mounting surface and the know-how.
• Actual bulb voltage listed in parenthesis.

They might as well learn something while they're trying to outlast you on eating those lima beans. Set the table with educational placemats and they'll be at least a touch smarter after dinner, even if their vegetable intake is low. These laminated, 12" x 17-3/8" mats have full-color fronts, black-and-white backs. Choose the United States Map, Stars & Constellations, the Periodic Table of Elements or The Metric System.

Nice little teaching magnet set for the primary grade classroom has (6) magnets in star, two-bar, horseshoe and ring shapes, all plastic coated in silver and red to mark the poles. Range in size from 1” to 3”, and include a few paper clips and small nails for demo purposes.

If the question is whether to tie a bunch of these giant latex professional weather balloons to a lawn chair, the answer is no. (The balloon bursts at about 82,000 feet anyway.) This is a true high altitude weather balloon, with plenty of fun, nonfatal uses. The cream-colored latex balloon is approx 40" dia when flaccid, you should pardon the expression, but has an 8-foot dia when inflated. The neck is 9" long x 1" dia. Scientists and meteorologists launch balloons to measure atmospheric conditions like wind speed and air pressure for weather forecasting, but clever inventors, teachers and the imaginative filmmaker are warned to launch the balloon carefully. The synthetic rubber material is delicate and not made to survive brushes with pavement, pine branches, or clumsy physics students. Red not available and only available in egg shell/cream color only.

You choose between our 2" square classroom demonstration slides. The diffraction grating slide has 500 lines per mm resolution and a wavelength chart; the linear polarized filter slide has a 1-3/8” x 15/16” window. Nice for classroom and home-schooling use. Made in the USA.

Classroom and Science Fair alert: Now you can order an 8-pack of metals and metal alloys for demonstration purposes. Each pack of 1" dia x 1/32" thick discs includes aluminum, bronze, brass, copper, n/silver (w/nickel), m/steel (mild: low carbon), stainless steel, and zinc. Composition of each is stamped on one side of the discs.

Ohaus made giant bow calipers. Use them to measure outside diameters (like balls, boxes, your head, your waist), inside diameters (like cylinders and boxes). They are 15" long when folded and even have a graduated side in MM to measure depth. A very cool teaching tool. Includes a teaching aid instruction sheet. Max outside diameter is 25" (635Cm) 

Same here. Try the Ferrofluid Magnetic Display, a little sealed bottle with virtually fluid nano-particles of ferrous metal suspended in liquid. You’ll get (4) powerful 1/2” dia x 3/16” neodymium disc magnets, (2) of them attached to chess-pawnish holders. Move the magnets in assorted combinations around the bottle for fascinating effects. Sort of the marriage of science with desk toys, but students can’t spill these particles all over the place.

The next best thing to lightning bolts! 200,000 volts of electrostatic energy created by our Van de Graaff generator. Measures 6-1/2” diameter by 15” tall, includes a spare belt and a set of instructions detailing lots of fun experiments. For grade 6 and up. This is not a toy and should be used under adult supervision. A great tool for teaching about electricity. For your convenience, we now have Lightning Belts: replacement belts to drive that overworked generator. Operates on Standard 120 VAC with the included 3' cord.