Mr. Carter is about to start a two-day lesson on subtraction of integers with his sixth-grade prealgebra students. He plans to use contextualized problems that will allow his students to develop an interpretation of subtraction that involves the idea of "difference." This article outlines one way to teach students develop number line…

Spatial abilities help students identify features of various shapes and the relationship that exists among these features. Being able to mentally manipulate images and tell what those images represent are important spatial skills. Research has highlighted the relationship between mathematics performance and spatial abilities. This article's…

This article describes an action research project in which a sixth-grade teacher engaged students in writing about their problem-solving efforts. The written mathematical work provided new artifacts for examining students' metacognitive and mathematical communication skills, prompting the teacher to make instructional changes to address students'…

The combined seventh-grade and eighth-grade class began each day with a mathematical reasoning question as a warm-up activity. One day's question was: Is the product of two odd numbers always an odd number? The students took sides on the issue, and the exercise ended in frustration. Reflecting on the frustration caused by this warm-up activity,…

Functions are one of the most important and powerful tools in mathematics because they allow the symbolic, visual, and verbal representation of relationships between variables. The power of functions, as well as the numerous real-world uses of functions, make them an important part of the development of algebraic reasoning in the middle grades.…

Students may be able to set up a relevant proportion and solve through cross multiplication. However, this ability may not reflect the desired mathematical understanding of the covarying relationship that exists between two variables or the equivalent relationship that exists between two ratios. Students who lack this understanding are likely to…

Mathematics is rich in visual representations. Such visual representations are the means by which mathematical patterns "are recorded and analyzed." With respect to "vocabulary" and "symbols," numerous educators have focused on issues inherent in the language of mathematics that influence students' success with mathematics communication.…

The eight mathematical practices explored in the Common Core Math Standards are the following: (1) Make sense of problems and persevere in solving them; (2) Reason abstractly and quantitatively; (3) Construct viable arguments and critique the reasoning of others; (4) Model with mathematics; (5) Use appropriate tools strategically; (6) Attend to…

On entering Mr. Wilson's seventh-grade classroom, the authors immediately noticed the students talking about mathematics and their teacher listening to them. To create an interactive learning environment that would stimulate and perpetuate discourse, Wilson discussed two main issues with his students: (1) What the students and teacher would do in…

There are two primary interpretations of the mean: as a leveler of data (Uccellini 1996, pp. 113-114) and as a balance point of a data set. Typically, both interpretations of the mean are ignored in elementary school and middle school curricula. They are replaced with a rote emphasis on calculation using the standard algorithm. When students are…

Small-group discussions are one tool that teachers in linguistically diverse classes can use to promote all students' participation in mathematical discussions. Although many teachers in such classes express reservations about using group work, numerous examples from research and practice have explored teachers successfully using group discussions…

Crime Scene for Mathematics Investigation (CSMI) was created as a small group, cooperative, self-selective grouping strategy to allow students to explore mathematics based on their own understanding and perceived readiness, much like the concept and application of literature circles in language arts. In essence, these self-chosen small groups met…

As the sole math teacher in his middle school, the first author has always worked hard to provide quality mathematical experiences for his students. In an era of accountability defined by standardized test scores, he has also closely monitored his students' performance on such tests. After a few years of hoping that scores would improve, he…

Learning mathematics is challenging. It requires discipline, logic, precision, perseverance, and accuracy. It can also be fun. When mathematics is set in a context that inspires students to want to solve interesting problems, students will have an intrinsic desire to learn the necessary skills to accomplish a specific goal. The game of Crypto! was…

Middle-grades students have a concept image of a circle, but they lack experience in the act of defining. The structure of definitions needs to include conditions that are necessary and sufficient. Most students are able to identify necessary conditions, but they have trouble determining if sufficient conditions are met. How do teachers engage…