BLUF: Any recommendations for session zero, game systems to run, and co-dming with teens?

As a bit of background:

I used to run Hero Kids games with my wife back when the kids were 8, 6, and 4. They enjoyed them and we occasionally run other games with them now, but the younger ones aren't as interested in them anymore, so getting them in has been more difficult. All of them have differing levels of ability to sit through a game, and keeping combat turns quick has been a key focus.

My eldest is now 12, and is interested in playing more TTRPGs and learning to DM her own games. She's been playing D&D 5e weekly with a group of teens at a FLGS, but she's probably one of the youngest ones there. She's also neurodivergent, as are several others in that group. So there's often been struggles with things not being done "the right way" as well as attention spans growing short and wandering. The gaming group has already grown too large and unruly and been split once, so now it's two different games meeting every other week each instead of one game meeting every week.

The owners of the FLGS have expressed interest in having other people help run games for teens there, and I'm interested in helping, but I'm less fond of D&D 5e myself, especially for teens with short attention spans. So my idea currently is to come up with a "Survey of TTRPGs" and just run one shots in multiple systems, and end with offering some games where interested teens can run a one shot and I'd just serve as co-dm with them. I'd be available to help plan, as well as to help run the game day of.

My thought process here is that experiencing several different systems would help expand their experience of play styles, and would hopefully make it easier for them to accept players at their table having different preferred play styles. The experience would also hopefully illustrate different situations and scenarios in play, and make it easier to accept new ideas at the table. To me, the ideal help for the ongoing situation is to have a group of teens willing and interested to run games for other teens, and my daughter is interested in being one of those teens but isn't comfortable doing so yet.

I want to start by coming up with a session zero that is geared for teens, and then do some very rules lite systems for the first few weeks. The goal being to introduce some role playing concepts and decision making options without a lot of rules involved up front, then work to other systems that have additional rules as time goes on. I imagine we'd start with something like Heroic Tales, work in Tiny D6 based games, look at some OSR type stuff, check out some PbtA, and end on D&D 5e and/or Pathfinder 2e. When we make it to the point of offering co-dm sessions, the kids could pick anything we'd run already as the base system.

My personal struggle is that I enjoy a lot of systems, and am interested in a lot more that I haven't gotten to play yet. So I've been trying to work several of those into this idea. I tried to work out a list of systems, and eventually had 13 one shots I was going to try and run, with multiple options in systems at basically every one of them (and multiple genres to boot), and I feel like it is probably just a bit too ambitious, and want to pare it back further.

So does anyone have:

• Any tips to offer for running games for teens (current group is ages 12-17),
• Suggestions for systems that have quick combat turns to help maintain the interest of short attention spans,
• Extra tips for Session Zeros that come up more often with teens than adults