The U.S. Supreme Court has observed: "It can hardly be argued that either student or teacher shed their constitutional rights to freedom of speech or expression at the schoolhouse gate."
The constitutional principle regarding symbols, music, art, drama or literature, whether in public school or in association with other public entities is simple — mix the secular and the sacred.
A school-sponsored concert on a public school campus which contains only Christian Christmas songs mixed with secular songs of the holiday make the presentation constitutional.
Public schools are not religious-free zones. Students may distribute religious Christmas cards and greet one another saying "Merry Christmas." If the school does not require uniforms, students may wear clothing with religious symbols or religious jewelry.
Courts have long recognized the historical, social and cultural significance of religion in our lives and in the world, generally.
I beg of everyone this Christmas to stand up for your freedom of speech and religion! Have a blessed Christmas.