My guitar teacher said to find something that needs to use economy picking so it's easier. But I don't know what to choose. Any ideas??
The intro to Sweet Child o' Mine - Guns n Roses. Not only will you get economy picking but also string skipping and dexterity. This one will impress folks to boot .

Yeah that is a great song. The riff isn't too hard, just practice it slowly at first.
"We weren’t too ambitious when we started out. We just wanted to be the biggest thing that ever walked the planet."
-- Steven Tyler
sweet child of mine is actually pretty difficult if you arent used to it but another good song is nevermores psalm of lyidia and thats pretty damn impressive to me and im sure you could do it if you practice good luck
the sweet child o mine intro is economy picked? i downpick every note and its a lot easier. i can do the intro with downpicking much easier cause i dont have to concentrate on the motion that much and the motion's fluid.