For help with your leaf identification project try these sites:
What Tree Is It? Identify by leaf, fruit, or name.
Temperate Deciduous Forest A simple site from the Missouri Botanical Garden
Key to Virginia Trees This site has many of the same trees found in Ohio and is easy to use.
Common Trees of Pennsylvania Also has many of the same trees found in Ohio.
Leaf Structure and Grouping Introduction to leaf shapes and how to identify them, from Penn State Universitys
Tree Images The Noble Foundation's gallery of photos of trees. Look up a tree by common name, scientific name or family name.
Why Do Leaves Change Color?
Tree Fact Sheets Detailed information on 680 different trees, searchable by common name or scientific name. (no color photos)