N.J. Stat. Ann. § 18A:36-14

No pupil of any public school, who shall be absent, by reason of observance of a religious holiday, from such school at any time when the same is in session, shall by reason of such absence be deprived of any award or of eligibility or opportunity to compete for any award, or of the right to take an alternate test or examination, for any which he missed by reason of such absence, if a written excuse signed by a parent of, or person standing in loco parentis to, the pupil be presented to the proper school authority.