Not sure where the school is, but if the weather permits, I would open the windows and put a fan in the window. A constant supply of fresh air won’t solve a mold problem but it will keep the levels down in the breathable air. This could provide some relief until it is all sorted out.
Also, contacting the health department to find out what your options are could be helpful. Those folks generally have great authority to investigate if they feel it is warranted.