Everyone knows that arithmetic is true: 2 + 2 = 4. But surprisingly, we don’t know why it’s true. By stepping outside the box of our usual way of thinking about numbers, my colleagues and I have ...

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 ...

In this tutorial, we demonstrate how to identify if a sequence is arithmetic. Learn how to calculate the difference between consecutive terms and verify whether the sequence follows a constant pattern ...