This is “Phase II”. Phase III will be when parents and supporters hold ‘alternative’ sporting events for just girls, ideally at the same dates and times as the public schools events.
Granted it is a huge and expensive hassle, but everything public school related is based on attendance. No attendance, no support, no money.
And if it is private, maybe in cooperation with charter and/or religious schools and home schools, it can include many things public schools would refuse to do, such as target shooting, archery, and Bible studies.
One problem Phase III might have is finding a venue to hold the events.
I am wondering...if enough students are in private or home or alternative schools could the voters float a law that outlawed school taxes or drastically cut them? Could it be countywide? Or statewide? If it was a county could refrain from paying taxes that might start a push in that direction. Cripple the public schools.