Do I need any of my evidence notarized?

Copies:

• Birth Certificate (Translated)
• University ID
• Letter from clinic stating how long I've been at the clinic (Has their logo, and a bunch of stamps from physicians and the clinic)
• Letter from an info seminar I attended (Has the directors signature/info and the universities name on top)
• High School diploma
• University diploma

i think the only evidance you need notorize will be the affidavit

I know for a fact that USCIS requires affidavits to be notarized for certain forms. Not sure about the forms for DACA. I would also advice to notarized any affidavit just to be safe. As maortiz said, your evidence doesn't need to be notarized.

Are letters from the clinic and university director considered affidavit's?

Only if they're sworn statements.

You only need the affadavit notorized. Anything else (diploma, transcript etc) with an OFFICIAL SEAL, STAMP or signature is already certified and so does not need to be notorized. I was told by a public notary that getting something already certified notorized defeats the purpose. haha