§ 59.09. Admission fees. In order that the educational influence of the planetarium shall reach as many persons as possible, the board shall not fix admission fees, at rates higher than are necessary to pay the cost of construction, operation, maintenance and repair of the planetarium and instruction in connection therewith, and reserves therefor, and to pay the principal of and interest on any bonds issued hereunder, and to meet the reserves and sinking funds provided for in any resolution authorizing such bonds. Classes from the public schools and colleges of the city of New York shall be admitted to the planetarium at such times and upon such days of the week and under such reasonable rules and regulations as the board shall prescribe.