Addition & subtraction strategies to solve two-digit equations using an open number line. In this lesson, students go over using different addition and subtraction strategies to solve two-digit ...

For all of the recent strides we’ve made in the math world—like a supercomputer finally solving the Sum of Three Cubes problem that puzzled mathematicians for 65 years—we’re forever crunching ...

Time to test your brain! Are you a puzzle person? Most of these hard math problems aren’t straightforward arithmetic. They challenge you to look at problems a different way, testing your logic and ...

A key part—though surely not the only part—of early-grades math is ensuring students get the basic arithmetic functions down and, beyond that, making sure they’re able to swiftly and automatically ...

Measure your hand. Create and use a line plot of hand span data to answer questions. Warm up with a Mystery Math Mistake to find the mistake made in counting up on a number line to subtract. Notice ...