This chapter discusses the use of tools and classroom technology and why they are not only helpful but essential to the teaching and learning of mathematics. It examines the use of hands-on manipulative tools in the classroom. Instead of teaching students the basic skills and then demonstrating an application at the end of a lesson or unit, teachers are encouraged to design lessons and experiences for students that use the skills in a meaningful way. Effective teachers are those who have knowledge of the mathematical content and the type of teaching strategies that are most effective in the classroom. A popular tool used for teaching mathematics is the computer spreadsheet. Research supports the use of spreadsheets in teaching mathematics, indicating that spreadsheets help students generalize patterns and make connections between arithmetic and algebra. A simple but extremely useful tool in the mathematics classroom is a document camera.