C-150 stalls
Stall / spin in take off?
This looks more like training accidents in take off and departure stall training. In this mode the cessna with full flaps and full (although low at 100 hp) power the little bird can get a little touchey. It is very common to spin over the top if the coordination is not good. A go around with full flaps is not likely with 40 deg. flap.
This sounds more like training accidents. The proper use of this much flap requires some training that would be absent if one trained in a 152 and then transitioned (?) to a 150.
The FAA limited the flaps to 30 deg since you can get into trouble with 40 if you were not trained for it.
For example the pilot must be trained to ptoperly fly the Cessna 150 where if trained ina Piper warrior the "pilot" needs almost no training at all.