N.J. Stat. Ann. § 18A:24-2

Any board of education may borrow upon its promissory note or notes bearing interest at not to exceed 6% per annum such sum or sums not exceeding 80% of the amount due it for tuition from any school district and upon assignment, as collateral, of the delinquent tuition and the tuition so assigned shall, when and as received, be applied to the repayment of the amount borrowed, with the interest, until the same has been fully repaid.