工读学校

工 = 二 + 丨 : Mnemonic symbol: a steel beam, since 工 looks like the cross section of a steel beam. In front of the engine ((e)ng1), Gitta Giraffe (gu) is doing some hard work: She's stacking a capacitor (二) on a dinosaur bone (丨) on a capacitor (二). She's not very successful, but then she gets the idea to use steel beams (工) as support.

读 = 卖 + 讠 : Doggy Dog finds an advertising column just inside the space station's entrance. He finds out that it's for sale: There is an price tag attached to it. He reads the price tag aloud: "woof woof woof woof!"

学 = 小 + 冖 + 子 : Xu Xian wants to study scienceology and learn more about daisies. Just inside the elevator's kitchen, he put some daisies into a prize cup and covered them with a cooking top. He wants to study the growth rate of the daisies depending on the pH of the water in the prize cup.

校 = 交 + 木 : In the aorta's bathroom, Marie Curie and Linus Pauling find their Christmas presents of a lifetime under a Christmas tree. They are given the gift of being able to go to school so that they can become accomplished scientists.