I think Loki would be really interesting as a teenager. He's already a bit of a mischievous character, and as a teen, he would probably be even more so. He might play pranks on the other Avengers - turned - teens and cause all sorts of chaos in their new high - school - like setting.
Peter Parker (Spiderman) could be the most interesting. Since he's already a teen in the regular story, seeing him interact with the adult Avengers who are now also teens would be great. He could be like the leader among them in terms of understanding the teen world, but at the same time, he would be in awe of the older heroes who are now his peers.
Natasha Romanoff as a teenager could be fascinating. As a teen, she would be even more of a mystery. She might use her skills in a more sneaky and unpredictable way. Also, her relationships with the other Avengers - turned - teens would be complex. Maybe she would be the one who tries to keep everyone in line while also dealing with her own teen insecurities.
Well, perhaps they are turned into teenagers due to some villain's new weapon. As teenagers, they start to view the world differently. Tony Stark as a teen might be more reckless and impulsive, causing some chaos within the team. They could also face typical teen issues like crushes. Steve Rogers might have a hard time adjusting to the modern teen culture of dating and social media while still being a hero.
Hulk would be the most hilarious. Imagine a huge, green cat with a short temper. He would probably be constantly knocking things over with his big cat paws and getting frustrated when he can't smash things as easily as he could in his normal form. His attempts to roar would come out as a strange meow - growl combination that would be both intimidating and comical at the same time.
Black Widow could be the most interesting. She has a mysterious past and a lot of skills in espionage and combat. Her teaching would be full of practical knowledge. She could teach students how to read people, how to be stealthy, and how to fight if necessary. Her no - nonsense attitude would make her a strict but effective teacher, and students would learn a lot about survival and self - preservation from her.
Tony Stark would be great. He's got a quick wit and would come up with the most outrageous and sarcastic answers during the game. His banter with the other Avengers would be really funny to read.
Captain America is a likely candidate. He has a strong moral compass and a sense of protectiveness. He would see it as his duty to take care of the baby. His old - fashioned values would make him a great caregiver, like making sure the baby has a proper upbringing even in the middle of all the chaos in the Avenger's world.
Thor would be a strong contender. His god - like strength and the power of Mjolnir, or Stormbreaker, could be very effective against the Titans. He could fly in and smash the Titans with his hammer, and his lightning powers could also do significant damage.
I think Captain America would be really popular. He has that classic good - looks and a strong sense of right and wrong. He'd be the kind of guy who stands up to bullies and is always there to help others. In high school, those are qualities that would make him well - liked. Also, his leadership skills would probably make him a natural fit for student council or leading group projects.
I think Thor would be the most interesting. If he turned into a large and powerful animal like a dragon, he could breathe fire and fly. His already - impressive strength and combat skills would be enhanced, and he could be a real force to be reckoned with. He could also use his dragon form to intimidate enemies and protect Asgard or Earth in a very different way.
Thor would be the most likely. Since Thor has a connection to Norse mythology already, he would be familiar with Sleipnir. He might see Sleipnir as a symbol of his home realm and would quickly bond with it. They could communicate in a way that the other Avengers can't, sharing stories of Asgard and the great battles there.
I think Thor and Groot would be an interesting pair. Thor is this powerful Asgardian with his hammer (or axe) and Groot is this gentle but strong plant - like being. They could have some really fun exchanges, like Thor trying to teach Groot some Asgardian sayings and Groot just responding with 'I am Groot' in his own cute way.