Do any of them have chew marks from insects? Do they have holes where a bug munched? These are leaf restaurants. Many different kinds of insects eat leaves. Were the insects big or little? How do you know?
What leaves to you eat? We eat all sorts of leaves such as lettuce, spinach, kale, and seaweed.
Look closely at the leaves and you might see bumps on them. The bumps are where insects make their homes. Many times it is a mother insect laying eggs under the skin of the leaf. Her babies will hatch out in a safe spot and burrow out or start eating the leaf. This is a leaf motel where the insect stays for a while.
If you want to save your leaves you can dry them in a book and then paste them in your own book or iron them between two pieces of wax paper. But before you do, make sure your leaf isn't an insect motel!