This short video and interactive assessment activity is designed to teach fifth graders about choosing the correct unit with liters or milliliters.

In this video segment from Cyberchase, the CyberSquad must locate a crystal with the highest fraction of orange color.

This short video and interactive assessment activity is designed to teach third graders about choosing the multiples of a given number up to 12.

This task suggests methods of introducing and continuing choral counting in the classroom.

Teachers (and then students) lead the class in chanting numbers from 1 to 120.

The purpose of this task is for students to find different pairs of numbers that sum to 7.

This task is primarily about volume and surface area, although it also gives students an early look at converting between measurements in scale models and the real objects they correspond to.

Although this task is fairly straightforward, it is worth noticing that it does not explicitly tell students to look for intersection points when they graph the circle and the line. Thus, in addition to assessing whether they can solve the system of equations, it is assessing a simple but important piece of conceptual understanding, namely the correspondence between intersection points of the two graphs and solutions of the system.

This task shows that the three perpendicular bisectors of the sides of a triangle all meet in a point, using the characterization of the perpendicular bisector of a line segment as the set of points equidistant from the two ends of the segment. The point so constructed is called the circumcenter of the triangle.

This short video and interactive assessment activity is designed to give fourth graders an overview of angles.

This short video and interactive assessment activity is designed to teach fourth graders about classifying all types of triangles by lengths of sides.

This short video and interactive assessment activity is designed to teach third graders about classifying all types of triangles by lengths of sides.

This short video and interactive assessment activity is designed to teach third graders an overview of triangle classifications.

This short video and interactive assessment activity is designed to teach fourth graders about classifying triangles based on equal sides.

This short video and interactive assessment activity is designed to teach third graders about classifying triangles based on equal sides.

This short video and interactive assessment activity is designed to give fourth graders an overview of triangle classifications.

In this task using a number line, students must partition the interval between 0 and 1 into eighths.

Students explore the definition of a function by playing an interactive game called "Club Function." The goal of the game is to be in the club! With students each assigned to be either a zebra or a rhinoceros, they group themselves according to the "rules" of the club function. After two minutes, students freeze in their groups, and if they are not correctly following the rules of the club function, then they are not allowed into the "club." Through this activity students come to understand that one x-coordinate can only have one corresponding y-coordinate while y-coordinates can have many x-coordinates that correspond to it.

This task assesses a student's ability to use the addition rule to compute a probability and to interpret a probability in context.

Students are exptected to identify the slope of the line with the unit rate in this real world problem.