Reading ahead for class is very good practice for subjects like math and science based subjects and will prevent the feelings of insecurity and confusion that often come up when learning new topics. However, if you are taking a philosophy of religion class and the teacher is basically spending an hour getting his point through, which he does seemingly word-for-word in the book(which he wrote), go ahead and don't give a damn about reading anything.
And also, I learned we emit radiation. Coooooool.
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