Students conduct Internet research to investigate the purpose and current functioning status of some of the largest dams throughout the world. They investigate the success or failure of eight dams and complete a worksheet. While researching the dams, they also gain an understanding of the scale of these structures by recording and comparing their reservoir capacities. Students come to understand that dams, like all engineered structures, have a finite lifespan and require ongoing maintenance and evaluation for their usefulness.

The purpose of this task is to help students explore the meaning of fraction division and to connect it to what they know about whole-number division.

This task asks the students to solve a real-world problem involving unit rates (data per unit time) using units that many teens and pre-teens have heard of but may not know the definition for. While the computations involved are not particularly complex, the units will be abstract for many students.

Simulate the original experiment that proved that electrons can behave as waves. Watch electrons diffract off a crystal of atoms, interfering with themselves to create peaks and troughs of probability.

This short video and interactive assessment activity is designed to teach fifth graders about determining the greatest quotient without calculation.

Students learn about and practice converting between fractions, decimals and percentages. Using a LEGO® MINDSTORMS® NXT robot and a touch sensor, each group inputs a fraction of its choosing. Team members convert this same fraction into a decimal, and then a percentage via hand calculations, and double check their work using the NXT robot. Then they observe the robot moving forward and record that distance. Students learn that the distance moved is a fraction of the full distance, based on the fraction that they input, so if they input ½, the robot moves half of the original distance. From this, students work backwards to compute the full distance. Groups then compete in a game in which they are challenged to move the robot as close as possible to a target distance by inputting a fraction into the NXT bot.

This short video and interactive assessment activity is designed to teach second graders about decomposing decimals into place values up to hundredths.

This short video and interactive assessment activity is designed to teach second graders about decomposing decimals into place values to tenths.

The primary purpose of this task is to illustrate certain aspects of the mathematics described in the A.SSE.1. The task has students look for structure in algebraic expressions related to a context, and asks them to relate that structure to the context. In particular, it is worth emphasizing that the task requires no algebraic manipulation from the students.

Why do objects like wood float in water? Does it depend on size? Create a custom object to explore the effects of mass and volume on density. Can you discover the relationship? Use the scale to measure the mass of an object, then hold the object under water to measure its volume. Can you identify all the mystery objects?

In this first part of a two-part lab activity, students use triple balance beams and graduated cylinders to take measurements and calculate the densities of several common, irregularly shaped objects with the purpose to resolve confusion about mass and density. After this activity, conduct the associated Density Column Lab - Part 2 activity before presenting the associated Density & Miscibility lesson for discussion about concepts that explain what students have observed.

Concluding a two-part lab activity, students use triple balance beams and graduated cylinders to take measurements and calculate densities of several household liquids and compare them to the densities of irregularly shaped objects (as determined in Part 1). Then they create density columns with the three liquids and four solid items to test their calculations and predictions of the different densities. Once their density columns are complete, students determine the effect of adding detergent to the columns. After this activity, present the associated Density & Miscibility lesson for a discussion about why the column layers do not mix.

This short video and interactive assessment activity is designed to teach fifth graders about one-step conversions between hundreds, tens, and ones.

This short video and interactive assessment activity is designed to teach fourth graders about completing the expanded forms of numbers (place values to 1,000).

This short video and interactive assessment activity is designed to teach second graders about identifying digit values in numbers (numbers to 10,000).

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important aspects of the task and its potential use.

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important aspects of the task and its potential use.

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important aspects of the task and its potential use.

This short video and interactive assessment activity is designed to teach third graders about describing patterns using letters.