Queensborough Community College and Houston Community College are two large, urban institutions that offer learning communities for their developmental math students, with the goals of accelerating students' progress through the math sequence and of helping them to perform better in college and ultimately earn degrees or certificates. They are two of six colleges participating in the National Center for Postsecondary Research's Learning Communities Demonstration, in which random assignment evaluations are being used to determine the effects of learning communities. At Queensborough, classes in all levels of developmental math were linked primarily with college-level classes, and at Houston, the lowest level of developmental math was linked with the college's student success class, designed to prepare students for the demands of college. A total of 1,034 students at Queensborough and 1,273 students at Houston entered the study between 2007 and 2009. The key findings presented in this report are: (1) Both Queensborough and Houston began by implementing a basic model of a one-semester developmental math learning community; (2) Learning community students attempted and passed their developmental math class at higher rates at both colleges; (3) In the semesters following students' participation in the program, impacts on developmental math progress were far less evident; and (4) On average, neither college's learning communities program had an impact on persistence in college or cumulative credits earned. With these results, a pattern is beginning to emerge in the experimental research on learning communities: Linked classes can have an impact on students' achievement during the program semester, but this effect diminishes over time. However, a fuller understanding will be gained as findings are released from the remaining three colleges in the demonstration. A final project synthesis report, including further follow-up, will be published in 2012. (Contains 2 figures and 2 footnotes.) [This paper was written with Rashida Welbeck. For the main report, see ED516646.]