This applied dissertation was designed to provide perceptual teacher data as well as summative testing data to educational leaders concerning the effects of implementing Investigations in Number, Data, and Space® (Investigations) in three Title I elementary school settings, two Title I schools, and one non-Title I school. Data collected during this dissertation will be of use to educational stakeholders in selecting mathematics programs for elementary age students. The purpose of this applied dissertation was to assess the effects of the Investigations program utilizing Stufflebeam's CIPP program evaluation model. End-of-grade math test data for third, fourth, and fifth grade from the 2010-2011 to 2013-2014 school years in a southeastern school district were analyzed along with teacher perceptual data. Teacher perceptions of the effectiveness of Investigations were measured by a survey developed by the researcher. Specific process and product research questions asked, "What are the teacher perceptions about the impact of Investigations on student achievement", "What were the unanticipated effects of the Investigations program on student academic development", and "What are the teacher perceptions about any unanticipated effects of Investigations on student academic development?" The survey data indicate that more than half of the teachers in the researched school district believed their opinions were not used in the selection of materials to implement Balanced Active Math strategies and the trainings offered did not adequately prepare them to deliver the Investigations program. All three schools dropped in proficiency following Investigations implementation in the 2012-2013 school year and increases in proficiency rates in the second year of implementation. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]