"Education is mostly speech, and parents have a constitutional right to choose the speech with which their children will be educated. They therefore cannot constitutionally be compelled, or even pressured, to make their children a captive audience for government indoctrination." - Philip Hamburger, teacher at Columbia Law School
https://www.wsj.com/articles/public-school-system-constitutional-private-mcauliffe-free-speech-11634928722?st=luht6renk4vn9eb&reflink=desktopwebshare_permalink