I love this topic. My daughter is getting close to gaming age.
*Consider the (I know someone will say something kooky, but here goes
) Pokemon KO rule. Instead of dying at 0-(-10), have the character knocked unconscious. The reasons are twofold. First, it allows them, as newbe players, to grow accustomed to their first character, and concentrate on the story and not rules such as dying, stabalization, etc. and might alleviate some of the disappointment of character death. I know, bad things happen, bad things shouldn't be avoided, I sound weak right? I am not saying that if they jump the top of a citadel they should survive (saving vs. death type situations). But, most normal damage inflicted could be done as subdual, not real.
I support even further with second reason. Since 3rd edition/d20 does not have a fast and clean character generation system in an abridged form (which I am still working on, hopefully soon guys
), similar to Basic D&D, character death would mean taking time away from gaming and rolling up a new character. You want to keep the action flowing. There will be plenty of Character death later on, but for their first few sessions, try to keep them interesed. Besides, they might get tired of being knocked out and waking up in a giant size bird cage suspended several hundred feet above the checkered pattern marble floor.
There are a couple of things I was considering for a pre-teen type game.
*Limit classes to arcane spellcasters for the PCs. Even if they want to be a fighter, that can come later with the easy multiclassing rules. In the first few tabletop games I played, I shyed away from magic-users cause I was not certain of the spell rules. Anyone can run a fighter, but to run a low HP, highly talented character takes a little practice. When they get the hang of the magic system, open up other classes.
Note: when I say arcane spellcasters, I mean wizards, sorcerers, AND bards. These classes allow the DM to craft situations that don't neccisarily lead to drawing steel. It allows them to find creative ways to best opponents. Instead of killing the guard of the captured princess, cast sleep, or darkness, etc.
The bard is very useful to pick up the slack in skills that the Wiz/Soc cannot have. Using the Pied Piper as inspiration, perhaps while the are adventuring the country side, then encounter a village where there is an infestation of giant rats or toads. The bard can use his music magic some how, to help the village and gain notority.
*If not using the above classes rule, consider one, (or two or three, but not too, too many) spells that all characters can cast. One staple of fairy tales if being put to sleep.
*If not using that rule, consider all classes able to use scrolls. The whole idea is to make them comfortable with the magic system.
*Use non-standard locations themselves to fascinate players. Imagine the bird cage above, a floating cloud castle, a giant city made of jade/gold/glass/etc., an underwater domed city, castles that only appear when the moon is full, etc. This age group may find it easiler to suspend disbeilief before they get old, jaded and cynical like us.
*Consider the focus of adventure trying to return home after some surprising event, such as a tornado, getting absorbed into a mirror, or lost in a snow storm only to come into a tropical clearing.
*Make all adversarial monsters nocturnal. They have all day to roam the countryside, but they better be near a castle by sundown, as camping is very, very dangerious!
*From the other big changes thread, make all magic items unique and give them each a name. There can only be one Caliph's flying carpet, or Short sword of spider's bane.
*Use lots of aerial encounters. Perhaps the campaign is set on a giant archepeligo, (sp.), and the most efficient way to travel from between islands is mounted on giant eagles, or flying carpets, or brooms of flying.
*Eliminate spell componets and in their place, make the requirment of an arcane focus item for all spells. Make the focus item different for individuals. One character uses a wand, one a staff, one a medallion, etc. Perhaps this is the motive for their first adventure, to find it, (like finding a familiar.)
I am sure I can think of more and will post them.