<p>I knew of one professor who assigned his own textbook to his class. He said he searched and couldn’t find any other book that was as good as his own. To deal with the ethical issues, he calculated how much he made in royalties from the student purchases and used it to fund a cookout for the students at the end of the semester. </p>
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<p>A previous edition of some textbooks might work if you can borrow someone else’s copy of the current book to see what is different and copy a few of those pages.</p>
<p>Look for looseleaf versions of textbooks that you put into 3 ring binders. They often are much cheaper. </p>