"Principles to Actions: Ensuring Mathematical Success for All" (NCTM 2014) gives teachers access to an insightful, research-informed framework that outlines ways to promote reasoning and sense making. Specifically, as students transition on their mathematical journey through middle school and beyond, their knowledge and use of…

The fifth-grade curriculum presents many opportunities to use students' prior mathematical knowledge as a way to bridge new and more difficult mathematical ideas. In this article, the authors document an area tiling task given to fifth-grade students to connect aspects of area measurement covered in earlier grades to grade-level standards such as:…

Building sets, video games, and scatterplots may seem unrelated, but when they are combined into a problem-based learning (PBL) lesson, these elements join to create a unique learning experience. PBL lessons drive instruction by focusing learning and activities around a central challenge or question while providing a relevant, captivating, and…

Middle school students need opportunities to craft informal mathematical arguments beyond justification of steps in an algorithm. Pentominoes provide an excellent vehicle for such activity. In this article, the authors describe an exploration with pentominoes that engaged a group of ninth-grade students in proportional reasoning, dilation, and…

Students' experiences with pattern blocks begin as early as preschool. At that time, they begin to develop an understanding of repetition by alternating the colored shapes to create AB, AAB, or ABC patterns. They experiment with area and symmetry by covering polygonal spaces using the fewest (or the greatest) number of pattern blocks possible or…

Classroom teachers try to provide opportunities for students to practice and use the algebra skills they are learning in ways that are nonroutine. They also want to help students connect the big ideas of math with the skills they are learning as part of the balance between understanding concepts and procedures. Math games can be used to accomplish…

Students are faced with many transitions in their middle school mathematics classes. To build knowledge, skills, and confidence in the key areas of algebra and geometry, students often need to practice using numbers and polygons in a variety of contexts. Teachers also want students to explore ideas from probability and statistics. Teachers know…

This article presents a lesson in which least common multiples helps students not only develop a perspective on an ancient culture but also draw on the cultural background of classmates. The Maya calendar received a lot of attention in the years leading up to December 21, 2012, because of the mythological end of "creation." Co-author…

Mathematics and science are natural partners. One of many examples of this partnership occurs when scientific observations are made, thus providing data that can be used for mathematical modeling. Developing mathematical relationships elucidates such scientific principles. This activity describes a data-collection activity in which students employ…

The mean can be interpreted as a fair-share value and as a balance point. Standards documents, including Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010), suggest focusing on both interpretations. In this article, the authors propose a sequence of five activities to help students develop these understandings of the mean, and they…

"Mathematical modeling of the physical world should be the central theme of physics instruction" (Hestenes 1987). Science teachers know this, but because of standardized state testing, many math teachers and some science teachers feel the need to focus on memorizing facts that will be on a multiple-choice test (Volante 2004). As a…

How many squares can be found on a typical 5 × 5 geoboard? Teachers who are unfamiliar with this question may wish to stop here and reflect a bit. The question can lead to wonderful student discourse: How can someone tell if something is a square? Should squares be counted that are the same size (but in a different location) or just different…

In mathematics, students should represent, model, and work with such real-world situations as those found in the physical world, the public policy realm, and society (CCSSI 2010). Additionally, students need to make decisions and be flexible enough to improve their decisions after analyzing realistic situations. The LEGO® Pets activity does just…

Numerous research articles and curricula standards maintain that learning is optimized when students are actively involved in the learning process by assimilating information and constructing their own meanings. The authors' experience with teaching probability concepts has shown that students struggle with concepts of counting. These…

Pattern blocks are inexpensive wooden, foam, or plastic manipulatives developed in the 1960s to help students build an understanding of shapes, proportions, equivalence, and fractions (EDC 1968). The colorful collection of basic shapes in classic pattern block kits affords opportunities for amazing puzzle-like problem-solving tasks and for…