Physics Kits for Kids

Thames & Kosmos publishes 62 experiments from a 64-piece kit with a 64-page full-color manual, rated ages 8+, on 2 AA batteries, at 16.8 x 11.5 x 2.1 inches and 2.4 lb. The published content runs from series and parallel circuits lighting a bulb, through push buttons and on-off switches, to “circuits that include a spinning motor, two switches, and up to three light bulbs”. The magnetism half covers which materials are magnetic, poles, magnetizing a metal, iron filings to “make invisible magnetic fields visible”, a magnetic pendulum, and a compass against Earth’s magnetic field.

The reason this leads is the ending, which the maker publishes outright: after a series of experiments with a sturdy electromagnet, the child builds a loudspeaker and an electromagnetic relay. Those two devices are the entire point of the subject — they are where electricity becomes magnetism and magnetism becomes motion and sound. Every other kit on this page stops before that join.

Sixty-two experiments against 64 pieces is also an unusually honest ratio. It means roughly one new experiment per component, which is what you get when a kit is built around explaining a subject rather than around a parts count. Compare that against the Snap Circuits line, where 300 or 500 projects come from 60 or 75 parts — a different and equally valid design, optimized for building rather than for understanding.

Published 2012, which matters less than it looks: the physics has not changed and neither has the kit. The honest cons are size and price. This is the biggest box here and the only one that needs a clear table rather than a lap. See what else a science kit needs.

Thames & Kosmos publishes 25 experiments from 12 pieces with a 48-page manual, rated 8+, on 2 AA batteries, at 10 x 11 x 2.5 inches and 1 lb. The motor is published as “made of transparent plastic to show how the inside components work”. The kit runs it on battery power first, then has the child “reconfigure the device to work in reverse as a hand-crank electric generator”.

Twenty-five experiments from twelve pieces is the highest ratio in this entire catalog, and it is worth understanding why rather than treating it as a bargain. This kit is not trying to build 25 things. It is trying to explain one thing 25 ways: a motor converts electricity into motion, a generator converts motion into electricity, and they are the same machine pointed in opposite directions.

That reversal is the best single idea available on this shelf, and the transparent casing is what makes it land. A child who has turned a crank and watched a bulb light has seen where electricity comes from, which is a question no amount of circuit building answers. It pairs naturally with solar and energy kits, where the same question gets a different answer.

The cons are real. Twelve pieces is twelve pieces, there is nothing to construct, and a child who wanted a building set will be disappointed inside an hour. It is also the cheapest kit here, which makes it a sensible second purchase rather than a first one.

Thames & Kosmos publishes 33 activities — its own phrase is “experiments and games” — from 42 pieces with a 48-page manual, rated 8+, batteries published as “N/A”, at 10 x 11 x 2.5 inches and 1.4 lbs. The published coverage is which materials are magnetic, poles and fields, “how Earth behaves like one giant magnet”, compasses, and building an electromagnet “to learn how electricity relates to magnetism”.

The specification worth paying for is a detail most buyers would skip: the iron filings come “in an enclosed transparent box”. Loose iron filings are the component every magnetism kit loses in week one — they stick to everything, they cannot be swept up, and once they are gone the best demonstration in the box is gone with them. Sealing them is the difference between a kit that still works in March and one that does not.

No batteries at all is the second quiet advantage. It is the only kit on this page that works the moment it is opened, which matters more on a birthday morning than any experiment count. See gifts that work straight out of the box.

The honest limit is scope. Thirty-three activities on one force, with a single electromagnet as the bridge to the other half of the subject. If the budget allows only one kit, the Electricity & Magnetism set above contains this one’s territory and then keeps going.

4M publishes 10 experiments and games in its KidzLabs Magnet Science set, item 00-03291, at an item size of 17 x 22 x 6 cm, rated ages 8 years and up, with no batteries required. It names the builds: “a super magnet racer, a compass yacht, a mysterious dangler”, a fishing game and a magnetic sculpture. The listing adds “over 25 pieces”; 4M itself publishes no piece count.

Ten is a small number and the page is not going to pretend otherwise. What it buys is the lowest price band on this page by a comfortable margin, which makes this the honest answer to a specific question: the child mentioned magnets once and you do not yet know whether it was a passing remark.

The named builds are also better than the count suggests. A fishing game and a magnetic sculpture are open-ended in a way a numbered experiment is not — nothing in the box says when the sculpture is finished. 4M publishes three awards for it, including a Parents’ Choice Recommended, which is the maker’s claim rather than ours.

Treat it as a stocking-sized purchase rather than a main gift. See small STEM gifts that travel and STEM gifts under $20.

Ravensburger publishes 122 pieces across 18 construction element types — base plates, height tiles, curves, junctions, switches, tracks, a vortex, a launch pad and a magnetic cannon among them — with 6 marbles and 9 included track designs, rated 8 and up.

It is on a physics page deliberately, because the electromagnetism kits above leave out half of school physics. Gravity, potential and kinetic energy, momentum, acceleration and the conversion of stored energy into motion are all mechanics, and no kit in this catalog teaches them with a manual. A marble run teaches them by consequence: build the drop too shallow and the marble stops.

The magnetic cannon is the genuine crossover. It stores energy in a magnetic field and releases it as speed, which is the same conversion the maglev kit demonstrates and the same one the loudspeaker in the Thames & Kosmos kit relies on — three very different boxes, one idea.

The honest con is that none of this is labeled. There is no manual explaining potential energy and no experiment numbered 14. If you want physics explained, buy a physics kit; if you want physics felt, this is the better object. See the GraviTrax review and mechanical toys for kids.