Probably one of the biggest tragedies in personal injury law for children is a thing called "immunity"... and school districts have lots of it.  Kids have literally been killed in the care of teachers and coaches, only for the school district to waive the immunity flag and walk away from negligent acts with no accountability.  However, it is possible, under very limited circumstances.  In the situation you describe... the history of the person(s) involved and the ramp could potentially break the immunity== but it will be very fact specific.  Your other issue is going to be statute of limitations-- which is looks like you've fallen past.  Again, there are some exceptions.  To see if the exceptions for immunity and statute of limitations would apply to your daughter's case, you need to gather as much info about the incident and medical issues and have a personal injury attorney review your case.  Try to find one that has had experience in suing governmental entities since this is a particularly challenging area of law.