The purpose of this study was to analyze the effectiveness of scripted biology curriculum as a means of providing students with the information required to increase content knowledge, while comparing curriculum developed by the teacher that utilizesthe Understanding by Design (UbD) framework (Wiggins & McTighe, 2005). The study used a mixed method, concurrent triangulation design which revealed that there was a significant difference between student growth from the pretest to the posttest. The teacher reflection logs and student focus groups identified two themes regarding science content knowledge: instructional/learning style and using discussion within the instructional cycle for both curricula. It was evident that the increase in content knowledge was associated with the utilization of discussion during the learning cycle. The teacher reflection logs and student focus groups also identified two themes when looking at the perception of the learning environment: the effect of teacher relationship on instruction and the effect of time on the learning environment. According to the instrument used, both groups of students showed growth, however, there was a larger gain among the students receiving the Understanding by Design curriculum. A major contributing factor for the growth among all students was the relationship the teacher had with them to meet their individual academic needs.