Discovery learning is one of the instructional strategies sometimes used to teach Algebra I. However, little research is available that includes investigation of the effects of incorporating the graphing calculator technology with discovery learning. This study was initiated to investigate two instructional approaches for teaching slope of a line in Algebra I. One approach involves the graphing calculator as a tool in a discovery learning setting. The second approach involves using the graphing calculator to reinforce traditional instruction. An urban public school division located in southeastern Virginia was the site for this investigation. Two Algebra I classes from each of two middle schools and two Algebra I classes from each of three high schools were involved in this study. The experimental groups completed a discovery learning activity, while the control groups used traditional instruction. This study is an investigation of whether there was a difference in student achievement in slope of a line when one discovery learning activity was completed prior to formal instruction. It was concluded that student achievement did not increase with the inclusion of one discovery learning based activity. Further study is needed to evaluate if discovery learning is effective if utilized throughout the unit on slope of a line, if additional professional development focused on discovery learning is necessary, or if a series of discovery learning activities would increase student achievement. [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.]