This research was inspired by a history of student difficulties in calculus, and innovation in response to those difficulties. The goals of the research were: first, to design an applet for students to explore local linearity; second, to redesign the curriculum of first semester calculus around introducing the derivative and the integral using local linearity, supported by technology and visualization, while delaying formal limits until the end of the semester; third, to design a framework to assess learning outcomes on the derivative; fourth, to assess the impact of the redesigned course on the learning and attitudes of students. The study also aimed to understand the impact of learner characteristics, the role of technology, and the role of visualization. Students in the study developed a robust knowledge of the derivative. There was clear evidence that the use of applets and graphs had a positive impact on student learning, and students were very positive about their use in this course.