The more I think about it, the more I realize that heather grey (the kind immortalized by every gym class since 1960---even rebel Danny Zuko wore sweats) is nearly as classic as denim. I want to wear it every day, and it seems to go with everything.
Don't be afraid to pick up a little boy's crewneck at Target. I might have.
Left to right, top to bottom: Crinkled Sweatshirt by Joie, Sweatshirt by Daftbird, Sweatshirt Pullover from Madewell, Grey Bow Sweatshirt by Manuelle et Guillaume, Parts of a Whole Pullover by Left of Center, Drapey Short Sleeve Sweatshirt from Loft.