Learn the basics of bowl turning To participate in any class, children less than 18 years of age must have a legal guardian or parent, who has signed the waiver agreement and the legal guardian or parent must supervise the child at all times during the entire event. Children less than 14 years of age cannot use any power tool (with the exception of random orbital sanders). Children 14 years of age and older may use power tools, but must do so under the direct supervision and guidance of the legal guardian or parent, who has signed the waiver agreement.