The frog magnet on the refrigerator fell and broke.
Alex likes to make fun stuff from old broken things.
She does a variety of experiments with the magnet, and finds things they stick to and things they don't.
She finds a box full of magnets on the workbench in the garage.
She discovers that magnets can both repel and attract each other.
She decides to use the repelling properties to make a flying carpet.
That leads to more experiments.