Any school district shall have power and authority, with approval of the Department of Education, to appropriate to the State Public School Building Authority any funds available for building purposes or for purposes set forth in sections 784.1 and 784.2¹ of this act. Any such funds which represent the proceeds of any general obligation bonds issued by the school district shall be used by the State Public School Building Authority for or toward the purpose or purposes for which such bonds were issued, and in the event that any such bonds were issued pursuant to a vote of the electors, any appropriation of such proceeds, as above set forth, shall not be deemed such a change of purpose from that for which such bonds were authorized as shall require the question to be again submitted to a vote of the electors under any existing law.