https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:atomic-models-and-periodicity/x2613d8165d88df5e:activity-what-makes-a-neon-sign-glow/a/activity-what-makes-a-neon-sign-glow 2026-01-14T23:20:41.344464701Z Activity: What makes a neon sign glow? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:chemical-bonding/x2613d8165d88df5e:activity/a/activity-what-hidden-trade-offs-exist-when-we-choose-aluminum-cans-versus-glass-bottles-for-packaging 2026-01-14T23:20:41.344464701Z Activity: What hidden trade-offs exist when we choose aluminum cans versus glass bottles for packaging? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:states-of-matter/x2613d8165d88df5e:activity-how-does-water-form-droplets-on-surfaces/a/activity-how-does-water-form-droplets-on-surfaces 2026-01-14T23:20:41.344464701Z Activity: How does water form droplets on surfaces? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:chemical-reactions/x2613d8165d88df5e:activity-how-can-a-big-log-turn-into-a-tiny-pile-of-ash-when-it-burns/a/activity-how-can-a-big-log-turn-into-a-tiny-pile-of-ash-when-it-burns 2026-01-14T23:20:41.344464701Z Activity: How can a big log turn into a tiny pile of ash when it burns? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:stoichiometry-and-the-mole/x2613d8165d88df5e:activity-how-does-the-international-space-station-produce-enough-oxygen-to-keep-the-astronauts-alive/a/activity-how-does-the-international-space-station-produce-enough-oxygen-to-keep-the-astronauts-alive 2026-01-14T23:20:41.344464701Z Activity: How does the International Space Station produce enough oxygen to keep the astronauts alive? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:solutions-acids-and-bases/x2613d8165d88df5e:activity-how-can-solubility-principles-help-us-detect-and-eliminate-chemical-contaminants-in-our-water-supply/a/activity-how-can-solubility-principles-help-us-detect-and-eliminate-chemical-contaminants-in-our-water-supply 2026-01-14T23:20:41.344464701Z Activity: How can solubility principles help us detect and eliminate chemical contaminants in our water supply? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:thermochemistry/x2613d8165d88df5e:activity-why-does-sand-at-the-beach-feel-hot-even-when-the-water-feels-cool/a/activity-why-does-sand-at-the-beach-feel-so-hot-even-when-the-water-feels-cool 2026-01-14T23:20:41.344464701Z Activity: Why does sand at the beach feel hot, even when the water feels cool? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:nuclear-chemistry-hs/x2613d8165d88df5e:activity-how-do-we-know-when-dinosaurs-lived-on-earth/a/activity-how-do-we-know-when-dinosaurs-lived-on-earth 2026-01-14T23:20:41.344464701Z Activity: How do we know when dinosaurs lived on Earth? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article