Fitbit Ace, Activity Tracker for Kids 8+

Price: $99.95 - $87.99
(as of Sep 07, 2020 21:16:59 UTC – Details)

From the manufacturer

Reward kids for hitting goals with celebratory messages and achievement badges. Kids can challenge others to step competitions, plus send each other messages or cheers
A showerproof tracker that survives splashes and spills with a secure, adjustable wristband for growing kids (one size). Designed for wrist sizes up to 155 mm/6.10 in.
Syncs stats wirelessly and automatically to iOS & Android devices and has a battery life up to 5 days (varies with use and other factors)
In the Fitbit app, parents create an account for their child under a family account (family account and parental consent required for children 12 and under)