T is for Teachers, yes you may serve as an Executive Committee Officer or be a member of the Board of Directors.

However, consideration should be taken when serving in a position requiring you to be a signatory on the separate bank account the PTA should have.

This question is usually asked when a PTA Leader wants to also meet the great need as a substitute teacher.

A representative at the State Department of Education explained there is a difference between a school employee and school board employee. 

Be sure the principal is aware of the dual positions and avoid participating in PTA activities while on the clock, unless the principal has approved it.