Are these really from the original patents?

Yes · every toy is redrawn from its real U.S. patent filing (patent drawings of that era are public domain), and each round’s reveal cites the exact patent number and year. The figures are simplified re-drawings in the site’s own style, not reproductions.

How do I know which piece is right?

The missing part is shown as a dashed outline in the drawing. Match the outline’s shape, size and orientation against the detached piece options · only one fits.

What does this train?

Part-whole visual reasoning and attention to structural detail · seeing how a familiar object decomposes into its working parts · plus a little history of the toys themselves.

Toy Assembly

本物の特許図面から描いた有名なおもちゃ · 欠けた部品を選んで完成させよう

FAQ

About Toy Assembly

Toy Assembly shows a famous toy · the LEGO brick, the Rubik’s Cube, the Slinky, the Etch A Sketch, the yo-yo, the Frisbee · redrawn as simplified line art from its real U.S. patent filing, with exactly one part removed. Pick the detached piece that completes the figure.

Every object cites the actual patent it was redrawn from (for example the LEGO brick’s U.S. Patent 3,005,282 from 1961, or the 1866 “whirligig” patent behind the yo-yo), and the reveal after each answer shows that citation · so every round teaches a small piece of design history.

Every round is generated deterministically from a seed. Runs entirely in your browser and works offline as a Progressive Web App.

FAQ

Are these really from the original patents?

Yes · every toy is redrawn from its real U.S. patent filing (patent drawings of that era are public domain), and each round’s reveal cites the exact patent number and year. The figures are simplified re-drawings in the site’s own style, not reproductions.
How do I know which piece is right?

The missing part is shown as a dashed outline in the drawing. Match the outline’s shape, size and orientation against the detached piece options · only one fits.
What does this train?

Part-whole visual reasoning and attention to structural detail · seeing how a familiar object decomposes into its working parts · plus a little history of the toys themselves.