This task illustrates the process of rearranging the terms of an expression to reveal different aspects about the quantity it represents, precisely the language being used in standard A-SSE.B.3.

This rich task is an excellent example of geometric concepts in a modeling situation and is accessible to all students. In this task, students will provide a sketch of a paper ice cream cone wrapper, use the sketch to develop a formula for the surface area of the wrapper, and estimate the maximum number of wrappers that could be cut from a rectangular piece of paper.

The purpose of this task is to engage students, probably working in groups, in a substantial and open-ended modeling problem. Students will have to brainstorm or research several relevant quantities, and incorporate these values into their solutions.

In the first video segment, we present a cartoon model of a weighted chain, which can be regarded as an approximation for a polymer under tension (e.g. a strand of DNA being stretched out using optical tweezers). The Hamiltonian and partition function for this system are described in the second segment. Finally, in the third segment, we calculate the average energy and elongation of the chain.

This short video and interactive assessment activity is designed to teach third graders an overview of rectangles, squares, circles and triangles.

This short video and interactive assessment activity is designed to teach first graders an overview of rectangles, squares, circles and triangles.

This short video and interactive assessment activity is designed to teach second graders an overview of rectangles, squares, circles and triangles.

This short video and interactive assessment activity is designed to teach fourth graders about selecting the quotient using given statements.

This is a video and assessment exercise aimed at helping first graders identify incorrect subtraction.

This short video and interactive assessment activity is designed to teach second graders about selecting the incorrect subtraction sentence (numbers up to 20).

This short video and interactive assessment activity is designed to teach second graders about selecting the correct addition sentence.

This short video and interactive assessment activity is designed to teach third graders about finding the incorrect equations.

This short video and interactive assessment activity is designed to teach fourth graders about identifyinging common factors.

This short video and interactive assessment activity is designed to teach second graders about identifying greater and lesser amounts.

This short video and interactive assessment activity is designed to teach fourth graders about comparing bills with pictures.

This short video and interactive assessment activity is designed to teach second graders an overview of ellipses, trapezoids, rhombi, and polygons.

This short video and interactive assessment activity is designed to teach third graders an overview of ellipses, trapezoids, rhombi, and polygons.

This short video and interactive assessment activity is designed to teach third graders about determining whether lines are perpendicular.

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

This short video and interactive assessment activity is designed to teach third graders about counting the number of basic 2d shapes in a composite figure.