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 ...

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 ...

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 ...

On his way to winning a Fields Medal, James Maynard has cut a path through simple-sounding questions about prime numbers that have stumped mathematicians for centuries. Number theorists, however, ...

The basic building blocks of the whole numbers remain mysterious.

In new research, mathematicians have narrowed down one of the biggest outstanding problems in math. Huge breakthroughs in math and science are usually the work of many people over many years. Seven ...