"SteveB" wrote in message
...
I want to build a project with my 8 and 10 year old grandsons while
they spend the time with us. I want it to be one for each of them,
and something that would last. I want it to be useful, or decorative
for their room. They might only get to do some filing or bending,
but something that they could help build.

Suggestions?

When I was that age I cut toy helicopter rotor disks out of tin can
lids. The launcher was string wound around a modified nail. I had to
fly them outside after my parents noticed the circles they carved in
the ceiling..

The plastic ones from the store didn't have enough inertia to keep
spinning as long as my steel ones, wouldn't glide sideways and bounce
off walls, and I could pull the string on mine harder to make them
spin faster. Never mind that the first few still had the sharp outer
edges left by the can opener. Even at that age I became concerned
about a free-flying spinning scalpel ricocheting around the room, and
learned how to file them smooth and marginally safer.