The minilessons in this two-part series are designed to reinforce elementary students math skills in engaging, problem-solving contexts. Requiring only 5 to 15 minutes to teach, these quick, engaging activities offer experiences in all of the content areas important to elementary mathematics: number, measurement, geometry, data analysis and probability, and algebra. Each resource of 27 classroom-tested lessons models how to develop several important math processes: problem solving, reasoning and proof, communication, connections, and representation. Each activity features a materials list, step-by-step teaching directions, a list of key questions to ask students during the lesson, a vignette of how the lesson actually unfolded in a classroom, and ideas for extending the activity throughout the year. Each book includes reproducibles.