I tell my students on the first day of class that I have at least two reasons for everything I do in class.
Most of the time they don’t call me on this. It would be fine if they did, though tiring.
However, having told them this, when the “Why do we have to do this?” whine comes up, I begin by reminding them that I don’t waste class time on anything that isn’t useful in at least two different ways. Then I explain the two ways that whatever they were fussing about is important. Often the things they fuss about are the ones I actually have three or four reasons for instituting.
“Why do we have to read each other’s work?”
1. Because you can see if you are on track.
2. You can help your neighbor see if they are on track.
3. If the work you read is particularly good, it gives you a bar to reach.
4. If the work you read is particularly bad, it helps you re-examine your own work to make sure you don’t look that terrible.
5. It teaches you critical evaluation skills that you can apply to your own writing.
6. It gives the student feedback that they might be more accepting of than mine. Or that might dovetail with mine and let them know that I am not the only one seeing the problem.
If you use this, though, make sure you have thought enough about your teaching strategies to know why the things you have included are important pedagogically.