It actually depends on what grade they are. If they are still HS kids, they likely are grade 9 or 8 or maybe 7 if they have been in it a while. That would mean they should be doing 5 hours of additional training a year. Most of the upper level referees that do both club and HS are grade 6 or 5 and require much more training as well as go to tournaments etc. and get much more training there from folks.