The students in Ms. Moscoso's second-grade class gather on the rug after recess, ready for one of their favorite math warm-ups: Choral Counting. Counting is an important part of doing mathematics throughout the school; students count collections (Schwerdtfeger and Chan 2007) and solve problems using a variety of strategies, many of which are…

When asked to determine the number of tens in twenty-five, most second graders who have had instruction on place value can quickly provide the correct answer of two. However, when asked to show how the numeral 2 is represented in a set of twenty-five objects, many children struggle to draw a connection between the digit 2 and twenty objects in the…

Mathematical modeling is an important and accessible process for elementary school students because it allows them to use mathematics to engage with the world and consider if and when to use it to help them reason about a situation. It fosters productive struggle and twenty-first-century skills that will aid them throughout their lifetime.

Several detours prompted me to find time in an overcrowded school day to incorporate important, powerful, daily, whole-class application of fact strategies. A few years ago, I embarked on a journey with my second graders, a journey through the strategies for mental computation of addition and subtraction facts. The focus of that journey was to…

Kyle, a kindergartner from a low-income family, is shown a set of three black dots on a white mat. His teacher then hides the dots with a small box lid and lays down an additional set of two dots. She pushes the two dots under the cover, one at a time. Kyle must now choose the number of dots "hiding" under the box from a set of four…

Counting all and counting on are distinct counting strategies that can be used to compute such quantities as the total number of objects in two sets (Wright, Martland, and Stafford 2010). Given five objects and three more objects, for example, children who use counting all to determine quantity will count both collections; that is, they count…

Textbooks, as well as classroom instruction, tend to present estimation as a stand-alone exercise, ignoring that "the process of estimation depends on the situation itself as well as the estimator." When taught this way, estimation is stripped of its power to help students judge the reasonableness of answers and make sense before,…

The advance of technology has caused many educators to question the time and energy expended for students to master the pencil-and-paper computation skills embodied in the long-division algorithm. In today's world, this mastery is truly a questionable goal. But understanding the conceptual infrastructure of the algorithm will add to students…

Discusses the relationship between computational fluency and number sense in early childhood mathematical development. (Author/NB)

Suggests that algorithms, both traditional and student-invented, are proper objects of study not only as tools for computation, but also for understanding the nature of the operations of arithmetic. (Author/NB)

Describes the work that students and teachers do to develop computational fluency for subtraction. Examines the orchestration of whole-class discourse and presents a collection of common strategies. (Author/NB)

Suggests ways to increase students' computational fluency using concrete materials, engaging tasks, and reflection time to increase number automaticity, flexibility in thinking about numbers, and use of efficient problem-solving strategies to find sums and differences. (Author/NB)

Provides an alternative to traditional instruction in multiplication and division to develop computational fluency in students. (Author/NB)

Discusses the importance of developing teachers' computational fluency so that they can effectively support their students' fluency work. Provides suggestions for helping teachers develop computational fluency with subtraction. (Author/NB)

Explains "Mathematical Mind Journeys," a lesson format that promotes computational fluency through variable practice that relies on mathematical memory rather than rote memorization. (Author/NB)