if your radio has endpoint (many do, most rtr radios dont though). u could set it that way. you should really. ur kids are smart i'm sure they'd rip it off lol. used to be with speedo's that had pot adjusters on it u could turn the high down that way. all thats gone with electronics. so ideally score somethin with endpoint in the radio so that it'll help them and be somethin u can use when u want to run.

some new rtrs come with speedos that have beginner modes too (think traxxas does that)

R