Should 4th through 6th graders, have the same

[John]

"I would prefer you call all the travelling" (A quote from Joe T)

I agree, but unfortunately we don't have 6 hours to play a 3rd or 4th grade game. Use discretion, call the obvious, have fun (because that's what it's all about anyway), and help the little kids have a great time. Just another opinion from an inexperienced referee (meaning I end up doing a lot of games in this age group).