I'm not too familiar with gaming with children, but I'd suggest starting with the Feywild. It fits the fairy (faerie) tales they're familiar with. If you want to run a spooky Halloween style adventure, pushing them into the Shadowfell would be cool. These planes are close enough to what they'd know to keep it in their realm of understanding. Outer Planes and Elemental Planes are complicated concepts that they may struggle with until they have a concept of planar travel.Oh but maybe my question was misleading...
I didn't mean to ask "how early in level", but instead "how early in the story" and specifically for children who are playing their first d&d campaign.
Our family D&D game with the kids is only at 4th level. They have just finished an adventure which ended with defeating the "goblin king", except it was duly noted that there are many goblins who self-appoint themselves such title, leaving it largely vague how important their accomplishment was.
I'm looking forward to preparing the next adventure for them, and I would like something different from the previous, which have all been pretty much about investigating a remote area to find a dungeon, and then clear such dungeon of its monsters. The adventure we just finished was my 5e conversion/adaptation of the old "Horror on the Hill", and even though I originally planned to get down to the last dungeon level and final monster, I cut it short half-way through the levels with a custom BBEG (the "goblin king" which is not in the original adventure) because it was getting too long (although, we could still continue down if I change my mind).
Ransacking my small chest of old adventures, many of them feeling a bit too similar, I was looking for something with more story/intrigue or with more environmental dangers and less straightforward combat. I am now reading through "Tales of the Outer Planes" and wondering if it's any good. The first adventure seems a bit railroaded and has almost zero combat, which is too little but can be spiced up with pseudorandom encounters. The problem is also that there is an NPC leading the PC which seems to negate all chances of intrigue and investigation, but without her/him it seems difficult to figure out anything.
Besides the challenge of finding a good adventure, my main question is whether dropping the bomb of planar travel this early makes it less special. The multiverse has always been one of my favourite concept in d&d, and I don't want to blow it too soon. Ideally I envision the progression of adventuring scope being local -> regional -> kingdom -> continental -> global -> universal (alternate material worlds) -> multiversal (worlds with different "laws of nature", afterlife, time travel...). Now we're talking about jumping from regional to multiversal.
I don't know, maybe it's just fine, but considering the first adventure of TotOP already brings the PC to meet someone at divine level, how can I then still inspire awe in my young players with anything more earthly?
For brand-new players, I'd say no earlier than 6 months of play. The Multiverse is a mind- and genre-bending concept, and it's best to let people play out their standard medieval-fantasy fantasies before turning the world upside down on them. Let them enjoy being Elves and Wizards in Middle Earth for a while before you open the door to all the weird planar stuff.Oh but maybe my question was misleading...
I didn't mean to ask "how early in level", but instead "how early in the story" and specifically for children who are playing their first d&d campaign.
For brand-new players, I'd say no earlier than 6 months of play. The Multiverse is a mind- and genre-bending concept, and it's best to let people play out their standard medieval-fantasy fantasies before turning the world upside down on them. Let them enjoy being Elves and Wizards in Middle Earth for a while before you open the door to all the weird planar stuff.
Besides the challenge of finding a good adventure, my main question is whether dropping the bomb of planar travel this early makes it less special. The multiverse has always been one of my favourite concept in d&d, and I don't want to blow it too soon. Ideally I envision the progression of adventuring scope being local -> regional -> kingdom -> continental -> global -> universal (alternate material worlds) -> multiversal (worlds with different "laws of nature", afterlife, time travel...). Now we're talking about jumping from regional to multiversal.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.