Build numbers with blocks. Ten ones make a ten, ten tens make a hundred. Play, solve missions, crack puzzles and beat the clock.
Start here. A number is built from blocks. A small cube is 1. Ten cubes stuck together make a long ten. Ten tens make a flat hundred. Ten hundreds make a big thousand cube.
Why columns? Each column has a job. The ones column counts single cubes, the tens column counts tens, and so on. The same digit means something different in a different column: in 303 the first 3 means three hundreds and the last 3 means three ones. The 0 in the middle is a place holder that says "no tens here".
Trading. You can never keep 10 in a column. Ten ones are traded for one ten, ten tens for one hundred. Going the other way, you can break one ten into ten ones. The amount stays the same, only the blocks change. This is the idea behind carrying and borrowing in addition and subtraction.
Try this above. Build 9, then add one more cube. What happens? Build 95 and make it 10 more. Which column changes? Build 300 and break one hundred into tens.
Place value means a digit's worth depends on its position. In 482 the 4 is worth 400, the 8 is worth 80 and the 2 is worth 2.
Pick the level, not the age. "Just starting" uses numbers up to 99, "I know the basics" goes up to 999 and "Challenge me" goes up to 9,999.
No. It is free and needs no account. Your stars are saved in your own browser.