Reliving the awkward phase glory days! As the remaining schoolkids headed back this week (how cute are J.Lo’s, Jessica Simpson’s, and Jessica Alba’s wee ones?!), we’ve seen our fair share of first-day photos. Now it seems older stars want in on the action by posting throwbacks of their school days. See John Mayer looking like a little businessman, Dax Shepard rocking some OP, and more gems.