In this lesson, third graders were asked how many degrees is a full rotation around a circle. After we gave students time and space to disagree, to make and test conjectures, and to explore, they reasoned about angle as turn and determined a full rotation is 360 degrees.
Amanda L. Cullen, Carrie A. Lawton, Crystal S. Patterson, and Craig J. Cullen
The paper discusses technology that can help students master four triangle centers -- circumcenter, incenter, orthocenter, and centroid. The technologies are a collection of web-based apps and dynamic geometry software. Through use of these technologies, multiple examples can be considered, which can lead students to generalizations about triangle centers.
Brandt S. Lapko
Teachers share success stories and ideas that stimulate thinking about the effective use of technology in K–grade 6 classrooms. This article describes how students can use available technology to communicate and share their thinking in popular media formats.
Kurt J. Rosenkrantz
Students say some amazing things. Back Talk highlights the learning of one or two students and their approach to solving a math problem or prompt. Each article includes the prompt used to initiate the discussion, a portion of dialogue, student work samples (when applicable) and teacher insights into the mathematical thinking of the students. In this month's episode, a six-year-old rising first grader uses a computer simulation to understand addition and subtraction on the number line.
Katherine A. G. Phelps
Fourth- and fifth-grade learners can use differentiated number sets within CGI problem structures to add and subtract fractions with unlike denominators.
Jennifer Suh and Padmanabhan Seshaiyer
Foundational in understanding place value and our decimal number system, this concept is explored through a practiced-based activity designed to develop teachers' technology knowledge for teaching mathematics. The activity focuses on number sense using online applets and various related models and representations.
Patricia O'Donnell and Amanda Frick
Do you remember clever, energetic Speedy Gonzales, “the fastest mouse in all Mexico,” one of the animated characters in the Warner Brothers Looney Tunes cartoon series? This month our “math by the month” activities, reminiscent of the spirited Speedy, will have your students calling ¡Ándale! ¡Ándale! ¡Arriba! ¡Arriba! (colloquial Spanish for “Come on! Hurry up!”) as they ask for more problem-solving scenarios based on this month's racing theme.