Young Children will thrive at whatever game you put them in. Obviously GameMastering for Elementary School kids is different than with Middle Schoolers and High Schoolers as well.
GMing for Elementary School Kids.
#1 Keep it Simple:
Miniatures and dungeon tiles will be more than magical to them. (expect them to play with the pieces, so don't use your best pieces.) Make Very simple character sheets. If you're playing D&D break it down to the simple numbers. Str +1, Dex +1, Con +0 etc. Use color coding so you can say "Add the Red number to your d20 roll." You could even make every weapon do d6 dmg. They wouldn't know the difference.
#2 Be Patient:
They aren't going to grasp every rule, and of course expect a lot of "Why" questions. Don't get mad if they don't want to be rail-roaded into the dungeon. Expect to have to do a lot of hand-holding for most children, asking if they want to go down the passageway or listen at the door. After a while they'll start doing that on their own.
#3 Be Flexible:
They are going to try to do wild, wild things. If you tell them they can't do any of it they will get frustrated and not want to play any more.
#4 Keep the Sessions SHORT:
Gnats have longer attention spans than kids, especially boys. Keep the sessions short and you will have more fun. I tried to make it one encounter at a time. Don't worry about rules so much, just play it off the top of your head, they won't know or remember if you didn't give them the benefit of the doubt.
#5 Realism isn't wanted or needed:
You're playing a fantasy game, the more simple the game the better, let them tell as much or as little as they want. Let the children narrate what happens if they want.
#6 Just Say NO to Murder:
Young minds: so while murder on TV is bad for kids, so it is in a role-playing game. Let them face skeletons, or bugs and spiders. But don't have them attempt to kill a human bandit or even an elf. As they mature, then throw them against non-humans, make orcs really mean and scary, so they are conquering a monster not a human being.
#7 Deus ex Machina: Let them win!
If they're about to lose the combat &be killed, make sure they're saved by someone, a Knight in shining armor sent by the King, or even a funny goblin that happens to be a powerful wizard
This is a perfect time to teach without making it feel like teaching. Math skills are especially important. Handwriting, not so much, save the penmanship lessons for late elementary school. About 5th grade is when I had the boys start writing their own character sheets.
#9 Don't Kill their Characters!:
#10 I repeat Don't Kill their Characters!!: C'mon they're little kids, you might traumatize them if you kill their pretend personality. Save mortality of characters for Middle School.
Next Week I'll discuss GMing for Middle school kids.