As an immigrant who couldn’t speak English when I first came to America at the age of 9, I would keep myself busy by building things like Thermite, which is basically mixture of rust and aluminum. Thermite is a great detonator for various bombs like TNT and whatnot, also used as emergency flashing guns.
Anyways, enough about me making thermite as a 9 year old, that was just plain, great chemistry fun, glad I didn’t lose an arm or leg during the process. This can be great for removing rust