Let me just start off by saying that I do not think that not doing homework is OK. However, it is definitely okay to take breaks or put off doing homework, as long as you get it done and (hopefully) still have most of your sanity by the end. Sometimes if your brain just isn't ready for equations or you've been reading textbooks so long that you're going cross-eyed, it is best that you do something to clear your mind and take it off schoolwork. Then you'll be ready to get back at it and get your work done. Here are some things that you can do instead of homework when you just need a break!
1. Watch an episode or two of something on Netflix
I do this quite often, but I tend to really struggle with the concept of just watching an episode or two (I tend to watch a season or two, but who's counting?). A couple episodes of "Friends" will clear your mind enough to get you back into the swing of things.
2. Read for fun
This may cause further headaches if you've been reading textbooks for hours, but otherwise is another good strategy. Again, limit yourself to half an hour to an hour of reading time.
3. Learn something new
The Internet is a wonderful thing. Go on YouTube and look up knitting or origami tutorials, something that will occupy your brain until you're ready to get back to that essay.
4. Take a walk
Sometimes, especially in nice weather, the problem is that you're cooped up inside and wanting to get out. So just go outside and enjoy the fresh air! Take advantage of the warm sunshine and then come inside to finish your work. (If you can take your schoolwork outside, even better!)
5. Play on your phone or cruise Facebook
These things are pretty mindless and you'll clear your mind, and finally stop thinking about that math problem you can't figure out. When you stop, you'll be able to look at the problem with fresh eyes.
6. Procrasti-baking
Take some time making a meal instead of throwing a ramen cup into the microwave. Pinterest has tons of recipes for you to try that are not expensive to make. Your tummy will enjoy a nice meal and it'll distract you, too.
7. Do something fun with friends
Go have lunch with a friend or go see a movie. Just leave time after to get your homework done!
8. YouTube
There are literally endless things to watch on YouTube that will distract (and entertain) you for a while.
9. Clean/rearrange your room
This is something that I often do while procrastinating and I don't even feel guilty about it because of how productive I feel doing it. I also find it to be much easier to do work in a clean room.
10. Take a nap
This one is probably my favorite. Sometimes, we just need to nap. If you're feeling sluggish, don't fight it. You'll be so much more productive when you wake up well rested.
For all of these things, it's also pretty essential that you know when to stop and get back to work. For your breaks, limit yourself to half an hour to two hours (depending on the activity) so you don't keep procrastinating (which is something we all struggle with). Just remember that it's okay to take breaks and award yourself with some fun time; you've earned it!