Maryland Education Section 6-503

      (a)      Public school employees may form, join, and participate in the activities of employee organizations of their own choice for the purpose of being represented on all matters that relate to salaries, wages, hours, and other working conditions.

      (b)      An employee organization may establish reasonable restrictions as to who may join and reasonable provisions for the dismissal of individuals from membership, except that these restrictions and provisions may not discriminate with regard to the terms or conditions of membership because of race, color, marital status, creed, sex, age, or national origin.