This study is an efficacy trial funded by a grant from the Institute of Education Sciences (IES) National Center for Education Research (NCER). Fifteen CPS high schools are receiving funding to implement two Algebra I credit recovery courses during the summer sessions of 2011 and 2012--one online and one face-to-face (f2f). These courses allow students to recover a 1/2 credit of Algebra I. The study is designed to address a set of research questions that address the following specific aims: (1) To test the efficacy of online Algebra I for credit recovery, compared with standard f2f Algebra I for credit recovery; (2) To determine the supporting classroom conditions under which online Algebra I for credit recovery yields higher efficacy; (3) To gauge the extent to which credit recovery can help at-risk students get back on track, relative to students who passed Algebra I in 9th grade; and (4) To gauge the effects of expanding summer credit recovery options through online courses. In this paper, the authors will focus on the impact of taking online Algebra I for credit recovery on shortterm outcomes for the first cohort of ninth-graders. These include credit attainment in the course and scores on an end-of-course algebra test and on the PLAN assessment (a standardized pre-ACT taken in fall of grade 10). Over the course of this 4-year study, we will continue to follow the first cohort of students, as well as a second cohort, through high school to examine long-term effects on future test scores, course-taking and likelihood of dropout. (Contains 1 table.)