This short video and interactive assessment activity is designed to teach fifth graders about adding and subtracting money using words.

This is a video overview of addition word problems (to sums of 100) for first graders.

This short video and interactive assessment activity is designed to teach second graders an overview of mixed operations (numbers to 1,000).

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

This short video and interactive assessment activity is designed to teach second graders about mixed operations: addition and subtraction i - word problems.

This short video and interactive assessment activity is designed to teach second graders about adding or subtracting lengths in one step.

This short video and interactive assessment activity is designed to teach fourth graders about adding or subtracting lengths in one step (english units).

This short video and interactive assessment activity is designed to teach second graders about adding and subtracting (numbers up to 20) - word problems.

This short video and interactive assessment activity is designed to teach fourth graders about adding of compound units of length (english units).

This short video and interactive assessment activity is designed to teach fourth graders about adding and subtracting fractions - word problems.

This short video and interactive assessment activity is designed to teach fifth graders about adding and subtracting fractions with different denominators.

This short video and interactive assessment activity is designed to teach fourth graders about adding 3 numbers - word problems.

This short video and interactive assessment activity is designed to teach fourth graders about adding capacities in compound units (english units).

This short video and interactive assessment activity is designed to teach fourth graders about adding decimals - word problems.

This short video and interactive assessment activity is designed to teach fifth graders about adding fractions with different denominators.

People using crutches have their hands occupied, which makes it difficult to carry books and other items they want to have handy. Student teams are challenged to design assistive devices that modify crutches to help people carry things such as books and school supplies. Given a list of constraints, including a device weight limit and minimum load capacity, groups brainstorm ideas and then make detailed plans for their best solutions. They create prototypes and then test for functionality by loading them and using them, making improvements with each iteration. At a concluding design expo, teams present their concepts and demonstrate their final prototype devices.

This short video and interactive assessment activity is designed to teach fifth graders about adding mixed numbers with common denominators.

This short video and interactive assessment activity is designed to teach fifth graders about adding, subtracting, multiplying and dividing.

This short video and interactive assessment activity is designed to teach fourth graders about adding, subtracting, multiplying and dividing.