How many shapes and sizes of leaves can you find on forest trees? One good answer would be ''lots and lots''!
A leaf can be simple, with a smooth, oval outline. It can be shaped like your open hand. It can have sharp spines, or rows of teeth along its edges. A leaf can be compound, which means that it is made up of several smaller leaflets.
A leaf can be very small or very big. The leaf of a tree fern can be 10 feet long. A leaf can be thin as a pine needle or two feet wide.
You can see the variety of leaves for yourself by making a leaf collection. Go to a garden, park, or forest and carefully pick a leaf from several different plants. Layer your leaves between sheets of newspaper and put a heavy book on top of the pile. In a few days, the leaves will be dry and you can glue them onto a sheet of plain or colored paper to create an interesting picture.
No matter what their size or shape, all leaves have the same job. They make food for the plant.
The part of a leaf that enables it to make food is the same part that makes a leaf green. It is a pigment called chlorophyll (CLORE-uh-fill). This amazing substance absorbs energy from sunlight so that the plant can make sugar from water and air.
Here's how it works. Plants absorb water by their roots. Leaves take from the air what we exhale: carbon dioxide. With the help of chlorophyll, green plants use energy from the sun, in a series of chemical reactions, to make sugar from carbon dioxide and water. This process, which makes it possible for plants to grow, is called photosynthesis (fo-to-SIN-thuh-sis), which means "making with light."
BONUS: Color the leaves