Guinea and Feather Apparatus, 20" Glass Tube Science at Home_Chemical Science securing a thermometer to any

securing a thermometer to any support rod at the angle needed for hands-free temperature monitoring during an experiment

Three-speed manual transmission with reverse in a clear-plated case

and 400 ppm

Seventy-eight-piece molecular model set with 45 atoms and 33 bonds for building basic organic and inorganic structures

letting students wire the panel directly to each load and watch how light powers different output devices

Guinea and Feather Apparatus, 20" Glass Tube Science at Home_Chemical Science securing a thermometer to anyDrops a dense object and a feather together inside a 20 inch evacuated glass tube, showing that air resistance not mass accounts for differences in fall time under gravity.