It would be awesome if fitbit made a tracker for kids. Something like the Garmin Vivofit JR. Maybe make it fun like the Leapfrog Leapband. The fitbit app could be changed to have a family setting so people can set up sub-profiles for their children. I'm sure I'm not the only person who has a child with a lot of interest in fitness trackers.
Moderator edit: Subject for clarity & labels