I always wonder when I see posts like this :-) What kind of a project?? Are we doing your homework for you?

No, your not doing my homework, I just had to find the leaves, and I had trouble identifying them, and I wanted to know if anyone could help me out.

Well, why don't we confirm or deny your guesses?
Here's a site that should help a great deal.

Here is a link that might be useful: leaf identification

I tired using that site, didn't help much.. is 11 a flowering dogwood?

The petiole is missing. Hard to ID with only a part of a leaf.
City and State or USDA zone can sometime aid in our identification.

Looks like zip code Levittown PA, not too far from me.
I cannot be certain these are correctly identified. Chris will help out, hopefully.

1. Platanus - sycamore or plane tree
2. Morus - mulberry
3.
4. This looks like an ivy leaf to me, Hedera helix.
5. Norway maple
6. Silver maple
7. Red maple
8. Sugar maple
9-12 ?
13 Quercus palustris - pin oak
14 Quercus - oak - black oak?
15 Acer palmatum - Japanese maple

3 Guessing Hawthorn
9 Red Maple (maybe another Maple)
10 Mulberry
12 Mulberry

What's a petiole?
And yeah, I live in Levittown, PA.

And thank you for your assistance Carol, hopefulyl I'll get more identifications, matching yours.

The petiole is the " stem" to the leaf, the part that joins the twig.

Here is a link that might be useful: {{gwi:343119}}

Here's a link to a good leaf picture of Cornus florida, flowering dogwood. The veins never quite reach the leaf margin ( edge).

Here is a link that might be useful: {{gwi:343120}}

11 Lindera benzoin (Spice bush)?