Every year, students use many books to write and draw on. Sometimes by the end of the year, not all of them get used up. I always ripped out the un-used pages and save them. Please, I ask that parents do the same and don't throw them out along with the book. Don't waste them. I always end up with piles and piles of them. So what do you do with those un-used pages, apart from scrap paper? I make them into junk journals and notebooks.
If you don't have any excess paper from your children's exercise books then there are other types of paper around you. I've used shopping paper bags, printed computer papers (these are usually printed on one side so I use the blank side), wrapping paper, gift-wraps, children's artworks on paper, yes and even old books that nobody wants.