The president or executive head of any institution of higher learning which has established a demonstration or practice school, subject to the approval of the board of trustees of state institutions of higher learning, shall have the power and authority to enter into contracts and agreements with the board of trustees of any school district providing for the attendance of pupils, or one or more, or parts of, grades, from the educable children of such school district at such demonstration or practice school. The board of trustees of any school district is hereby authorized and empowered to enter into contracts and agreements with the president or executive head of an institution of higher learning for such purpose. All such contracts shall be upon such terms and conditions as may be agreed upon by and between the president or executive head of the institution of higher learning and the board of trustees of the school district involved.