Nand2tetris

Computer from first principles

Bird water feeder

Attachment design

Hydrulivc power ganeration

Magnet. Water wheel

Math multiplication model

Use sticks

Newton disc with yr name

See yr name as it rotates

Levitating pencil

Rtn gift with attachmant and magnets

Daily receipt collector

Alternative to existing one

Seeder for Kolpe

You can sow with this.

Cycel Kolpe

Use this for activities in the small field

Center of Gravity Toy

Center of Gravity based Toys

Use following to create a toy

1. Eraser
2. Pencil