In this video, several adorable kitties get a lesson in basic physics when they become intensely fascinated with a kinetic motion desk toy. We hope you’re paying attention, kitties. There will be a test later.

The toy, which is called a Newton’s cradle, demonstrates conservation of momentum and energy via a series of swinging spheres suspended by wires. In particular, it proves that every action has an equal and opposite reaction, which is an important concept that Albert Einstein used when he developed the theory of relativity.

Of course, the kitties don’t know any of this and probably couldn’t care less about science as they bat the spheres back and forth. All they know is that it’s shiny, makes an awesome clacking noise and demands to be played with. Way to go, kitties! Never let book learning kill your fun.