What are the regulations around flying these? I remember doing it as a kid, but I could also walk to the store as a kid and play unsupervised with fireworks.
(Many model rockets don't get above 500 feet, so they never can even get into controlled airspace (usually 1200 ft above ground level) unless you're launching at an airport, which can be totally legal depending on where you are - most places have model rocket clubs and you can find where you can launch)
Being in California, I'm going to assume that county permit to launch a $20 toy 300 feet will be harder to get than FAA permits are for SpaceX to launch rockets the size of buildings to orbit.