Your logic is sound.<quoted text>The way I read the post, the point was that prayers that disrupt the educational process are not constitutionally protected, not that they violate the Constitution. The difference is not even all that subtle. Since they are not so protected, school policies that limit or forbid disruptive prayers are valid and may be enforced.
Saying grace at the cafeteria table is thus protected, while loudly reciting the 23rd psalm during math class is not. The student who does the former should be left alone while doing the latter can (and should) result in disciplinary action.
I agree with you.