Crouch face-down and protect your head with your arms. A bath tub may offer a shell of partial protection. If none of you are pretending to be a skaters currently, you aren't posers. This mobile-home safety video from the State of Missouri may be useful in developing your plan. You need to take immediate action to protect yourself and others around you.
What if I ask some of my friends if they want to learn to skate?
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Ask who their favorite skaters and skate brands are. Question them about their board. To them, skateboarding is mostly a fashion statement and they have no interest in actually riding. But the shoes do matter, I'd say. If possible, seek shelter in a sturdy building. Crouch low, head down, and protect the back of your head with your arms.