arithmetic
Adding and Subtracting Integers tool/game-Integer Heights
Why is 2 − (−3) bigger than 2? Balloons are +1, weights are −1, and taking away a weight makes the balloon rise. The big idea, zero pairs, a free number talk for grades 6 and 7, and Integer Heights, a self-checking digital game.
arithmetic
Decimal Place Value with Base-Ten Blocks and Number Lines: Build a Decimal
Build a Decimal is a no-prep digital tool for decimal place value: students build tenths, hundredths and thousandths with base-ten blocks, with wholes and parts kept apart, and see each number in words, as a fraction, in expanded form and on a number line.