Waiver of Liability Most Likely Won't Be Enforced in Virginia if Personal Injury Happens
Although Jumpology's form is very clear, I personally do not believe it would hold up in court. At least not here in Virginia. For at least 100 years, the Supreme Court of Virginia has refused to enforce pre-injury "releases" or "waivers" of liability that purport to release a company from liability for hurting another person. Such forms and contracts are considered to violate public policy. Another issue is that children, particularly those under the age of 16 in Virginia, are not held to as high of a "standard of care" as adults. In non-lawyer talk, it is difficult to argue in Virginia that a child was "negligent" in causing his or her own injury. So even if a child was at a facility like Jumpology and was himself acting "negligently", that negligence would likely not cancel out Jumpology's own negligence.
It is important to note, however, that the law on pre-injury releases is different in other states. Just across the state line in Maryland, for example, the general rule is that pre-injury releases are enforceable. Although there are some exceptions to that rule, the Maryland Court of Appeals made clear in a 2013 case that a parent can waive their child’s legal claims for negligently-caused injuries by signing a pre-injury release on their child’s behalf.