The purpose of this task is to have students add fractions with unlike denominators and divide a unit fraction by a whole number.

In this challenging instructional task students relate addition and subtraction problems to money and to situations and goals related to saving money.

Students learn how different characteristics of shapes—side lengths, perimeter and area—change when the shapes are scaled, either enlarged or reduced. Student pairs conduct a “scaling investigation” to measure and calculate shape dimensions (rectangle, quarter circle, triangle; lengths, perimeters, areas) from a bedroom floorplan provided at three scales. They analyze their data to notice the mathematical relationships that hold true during the scaling process. They see how this can be useful in real-world situations like when engineers design wearable or implantable biosensors. This prepares students for the associated activity in which they use this knowledge to help them reduce or enlarge their drawings as part of the process of designing their own wearables products. Pre/post-activity quizzes, a worksheet and wrap-up concepts handout are provided.

This word problem may be used for instructional or assessment purposes, depending on where students are in their understanding of addition and how the teacher supports them.

The purpose of this task is to help students see that 4_(9+2) is four times as big as (9+2). Though this task may seem very simple, it provides students and teachers with a very useful visual for interpreting an expression without evaluating it.

This short video and interactive assessment activity is designed to teach fifth graders about selecting the greatest value.

This short video and interactive assessment activity is designed to teach fourth graders about selecting the incorrect statement.

This short video and interactive assessment activity is designed to teach fourth graders about selecting the numbers from a given set.

Students gain experience and practice with three types of word problems using the "Take From" context: result unknown, change unknown, and start unknown.

This short video and interactive assessment activity is designed to teach third graders about shortening multiplication expressions (associative property).

Build coin expressions, then exchange them for variable expressions. Simplify and evaluate expressions until you are ready to test your understanding of equivalent expressions in the game!

This short video and interactive assessment activity is designed to teach second graders about solving decimal word puzzles.

This short video and interactive assessment activity is designed to teach fourth graders about solving length and distance problems involving time - word problems.

This short video and interactive assessment activity is designed to teach fifth graders about solving length and distance problems involving time - word problems.

This short video and interactive assessment activity is designed to teach third graders about solving multi-step problems involving time.

This short video and interactive assessment activity is designed to teach third graders about solving for elapsed time related to rate.

This short video and interactive assessment activity is designed to teach fourth graders about solving for elapsed time related to rate.

This short video and interactive assessment activity is designed to teach third graders about solving for elapsed time in a sequence of events - word problems.

This is a text that covers the standard topics in a sophomore-level course in discrete mathematics: logic, sets, proof techniques, basic number theory, functions, relations, and elementary combinatorics, with an emphasis on motivation. It explains and clarifies the unwritten conventions in mathematics, and guides the students through a detailed discussion on how a proof is revised from its draft to a final polished form. Hands-on exercises help students understand a concept soon after learning it. The text adopts a spiral approach: many topics are revisited multiple times, sometimes from a different perspective or at a higher level of complexity. The goal is to slowly develop students’ problem-solving and writing skills.

This task uses language, "half of the stamps," that students in Grade 5 will come to associate with multiplication by the fraction 12. In Grade 3, many students will understand half of 120 to mean the number obtained by dividing 120 by 2. For students who are unfamiliar with this language the task provides a preparation for the later understanding that a fraction of a quantity is that fraction times the quantity.