The validity and reliability of Technological Pedagogical Content Knowledge (TPACK) as a framework to measure the extent to which teachers can teach with technology hinges on the ability to aggregate results across empirical studies. The results of data collected using the survey of pre-service teacher knowledge of teaching with technology (TKTT) were synthesized using confidence intervals (CIs). Mean pre-service teacher TPACK point estimates were characterized by graphing CIs across studies from 2009 until 2011. The results present approximations of TPACK population parameters and implications for researchers and teacher educators.