HVAC filters are primarily designed to keep the system clear of dust and other debris, not to filter the air in the way you are thinking. You can bet your school uses the cheapest filters available, both for cost reasons and the fact that it is almost certainly what the HVAC system was designed to use.
Do you have any proof that the filters are unsafe? Do you have proof that your health issues weren't caused by something else?
Sounds to me like you are chomping at the bit to walk into your sup's office half-cocked and are not going to be happy with the result.