School of hard knocks: I'm a grad
And that all-blue Yankee is my graduation cap

from T.I. (Ft. Jay Z, Kanye West & Lil Wayne) – Swagga Like Us Lyrics on Rap Genius

Meaning

New York is the School of Hard Knocks. Jay said so in A Lil Sumthing the streets taught him more than Berkeley would as said in Hello Brooklyn 2.0 so when he got older, he Graduated from the streets, but always will feel close to the hood with that New York Yankees Hat.

Jay “made the Yankee hat more famous than a Yankee can”

This is also a reference to the Crip gang that rocks blue colors. Jay carries this over into the next few lines.

To help improve the meaning of these lyrics, visit “Swagga Like Us” by T.I. (Ft. Jay Z, Kanye West & Lil Wayne) Lyrics and leave a comment on the lyrics box