Insurance companies often ask what you harrassment and sexual abuse policies are. Rates vary according to what they are. The presence of the contract may be an indicator that you dance studio is carrying other insurance to provide coverage if you are injured as well. It's harder and harder to get an affordable policy with a good insurance company these days. The cost of providing accident coverage on children has skyrocketed. Claims of sexual abuse have pushed up the rates on all coverage for children. It's a mixed mess. What's really scary are the forms that ask you to sign release forms if you should be injured at an event or facility.
And really, the insurance issue where kids are concerned makes me think the smart thing is not to teach children. The amount of background checks and paranoia involved with them now really is more trouble than it's worth in most cases.
Personally, I like the policy "We're all adults here." Nine out of ten instructors aren't dumb enough to risk income loss on poor decisions. The ones that are tend to go out of business.