The goal of this article is to generate a portrait of the evidence on instruction that identifies strengths and gaps in the literature and that summarizes what this research base says about the relationship between classroom instruction and student outcomes. It was found that more than half the studies used data more than a decade old; few studies examined instruction during important transition years such as sixth and ninth grade; and subject area emphasis was lopsided, with mathematics and science instruction receiving much greater attention than English/Language Arts and Social Studies. The summary also revealed a repeated finding of low-SES students receiving diminished learning opportunities than more affluent peers.