This does seem like an overly strict interpretation of the law. I'm not a lawyer, but I think you can argue that you are donating, for example, bus services for the field trip rather than money to pay for bus services. Try talking to neighboring school districts to see how they handle this situation. (You could start by talking to PTO leaders at schools in those districts.) If you can document that other districts aren't setting such a strict policy, and demonstrate that the policy is a significant hinderance to your group and the school, you might be able to get it overturned.
- Craig
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