Graphing calculators have become one of the most widely adopted technologies in education because they are a proven-effective, affordable handheld device with direct linkages to curricula. A robust and consistent body of research shows that graphing calculators can effectively support mathematics learning and democratize access to complex mathematical concepts. Graphing calculators enable students to explore connections across multiple representations. Recent extensions support formative assessment via a wireless network. Graphing calculators are aligned with existing standards and curricula and support valuable pedagogical practices, such as increasing attention to conceptual understanding and problem solving strategies by offloading laborious computations. Innovators who want to provide new technologies that will have a real impact on learning would do well to heed the lessons and successes of the graphing calculator.