I haven't been DM since college... that's war roughly in 1995... 13 years ago.
I've offered one of my friends to DM for his 10 year-old boy and a few of his friends. They never played real role playing games.
I've been obsessed by the idea ever since.
I had prepared a small scenario which basically has them killing rats before getting entangled in a kidnapping story involving kobolds.
Turns out I hadn't read the dungeon master's guide 'till the end, because the scenario I was building was already built for me there - I just had to adapt it.
So I did and I play-tested it today, Marianne (awesome mother of my now-awesome and soon-to-be-awesome children) was roleplaying... the whole party.
First thing: I'm a rusty DM. Not enough confidence, so I bombed most of my planned role playing scenes - that's no biggie. Just have to practice my improvisation skills a bit.
Second thing: this is going to be way to long. I don't know what's the stamina of 10 year olds when it comes to DnD, but that thing could take 6 hours with one person deciding for the whole party... one person already moderately at ease with the rules.
So I think I'll have to forget the rats and cut the kobold adventure short a few rooms - or at least be prepared to cut everything short and provide a story ending.
Playtesting allowed me to figure our which information the players will need and not need - so I'll be able to adjust the simplified player sheets and power cards I prepared for them (more work!).
Playtesting also brought a few rules questions:
Does using second wind cause opportunity attacks?
As far as I can tell: no. Using second wind means you're concentrating on defense (while spending a healing surge).
What is the minimum distance from target for a ranged attack to work (using a bow)?
Target must not be adjacent - you can't use a range weapon as a melee weapon..
What's the difference between blast and burst?
Burst does not covert the point of origin. Bast does.