One-third of all net funds when received pursuant to Sections 40-20-8(c)(3) and 40-20-8(c)(4), by Escambia County from the severance tax levied, pursuant to Section 40-20-2, shall be paid to the Escambia County Board of Education, to be used for educational purposes and to be distributed as follows: Each public board of education, now in existence or hereafter created in Escambia County, shall receive a pro rata share of the monies based upon the relation its average enrollment in its schools during the preceding school year bears to the average enrollment of all the public schools in Escambia County.