Go out into the world and collect interesting leaves and twigs. You can shoot close-ups of them in the field, but you will have better control over the images if you bring them to a place where you can photograph them against a neutral background, isolating the image. If you have the facilities to light the subject evenly you will save some trouble later. If you only have a front flash you will get a shadow, but it is not too hard to get rid of, and sometimes it is useful to include it.

You may want to include stones or other natural objects placed so as to tell a story or suggest an idea. I do this all the time and have come up with some results I like a lot.This is a really simple way to make pictures that are more than just photos. You don't have to stick to leaves; you can use sticks, rocks, dirt, grass, tree bark, anything natural. Use them singly or in groups and illustrate a story for kids or adults.

The next phase is to work on your photos in some program such as Photoshop where you can draw on the picture. It is not hard to find pictures of leaves or other natural objects which resemble animals or people in action. You can enhance these by adding eyes, nose, etc. You can draw these add-ons yourself or snip them from other photographs of people or animals and place them strategically on the objects you are creating.

It is easy to juxtapose two or more leaves or twigs or other objects so that they seem to be having a conversation or in some other way are relating to each other. You can then caption the pictures or even write on the image so that it appears to be a cartoon with talking bubbles. This is easy to do with Photoshop and other applications.

Once you have collected a bunch of these items, you can publish them on a blog using the free services of Blogger or others on the web. This is a good way to share your creations. Another way is to put them up on Picasia or another of the web storage sites available for free. I like the blog approach myself. Good luck.