How can schools respond to the call to equip all students with the math skills required in college and the workforce when students are working at widely varying skill levels? Offering extended instructional time in algebra, or double-dose instruction, offers one potential solution to this dilemma and has become an increasingly popular approach for supporting students in high school math. Nearly half of large urban districts report double-period math instruction as the most common form of support for students with lower skills. Yet, despite the popularity of the double-dose strategy, there has been little research on the implementation of these reforms, or on their effectiveness. This policy brief summarizes the key findings from CCSR's (Consortium on Chicago School Research's) study of a double-dose algebra policy in Chicago and highlights implications for schools, districts, and policymakers. (Contains 2 figures and 22 footnotes.)