I am thinking in the 50 range.
Definitely keep picking up one as a weapon. See how the other kids like their buddies skull swung into their face.
... Bet they didn't teach that move at Barney camp!
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Now if these are super-intelligent 5 year olds who would actually be able to be cognisant of the training they receive and therefore attack in an organized manner then I would say in the 30 range.
If they were like me when I was 5 (but still would not be put off by the violence) then at least 50. When you need a break you could just jog in circles. Then turn around and begin the banger kicks.
Now I am going to be wary of 5-year olds in the street. Sneaky little scheming bas**rds ...
