The average cost of supplies required for elementary grades is about $26 for around a dozen items, but the cost can range from less than $5 to more than $80. The average cost in middle school was $52 to $60 for roughly 17 items, with the cost ranging from $13 to more than $150.The average cost for high school lists was $74 per student, and costs ranged from $21 to over $135 per student.The total out-of-pocket cost to parents for school-requested supplies in New York State is estimated to be $123 million.he average cost in middle school was $52 to $60 for roughly 17 items, with the cost ranging from $13 to more than $150. The average cost for high school lists was $74 per student, and costs ranged from $21 to over $135 per student.