Thanks everyone. My 15-year-old will likely have employment next summer, but thus far this is not earned income from an employer. Mostly it is gifts from family, earnings for grades and some chores around the house that they do in addition to their regular chores. We will definitely get them started with an IRA setup once they are earning employee income.
Synchrony looks good, but the lack of ATM reimbursement makes me wonder if I'd just be better throwing in the 1% myself and setting them up with a local credit union or Schwab (who reimburses for ATM fees). The idea is obviously NOT for them to take it out anyway, so I'll have to consider whether thats even an issue.
So, no one has mentioned Betterment... I know the $36/year is high compared to their automated deposit services accounts, but I'd love to get them interested in investing too.