Yes, the teacher can do that, and it is not illegal. Tell your daughter she can write in her journal when she gets home. The teacher was perfectly within her rights, and neither the teacher or the school did anything in derogation of the law.
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Teachers in most states are permitted to use that amount of force necessary to maintain discipline and order in the classroom. A student has no expectation of privacy in the classroom regarding documents or writings. If your daughter was writing in a private journal she may have a semblance of an argument for privacy, but even that would likely not avoid the teacher's right/responsibility to maintain order in the class.
Best of luck!
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