Dividing by 100 or 1000
When a number is divided by 100, each part of that number becomes 100 times smaller. If we break this down, it is the same as becoming 10 times smaller, then 10 times smaller again. So a thousand becomes a hundred and then a ten, and a hundred becomes a ten then a one. This can easily be seen using Dienes.
Using a place value grid, we can see that the digits move two places to the right as they are divided by 100, representing how the value of each has become 100 times smaller.
When dividing by 1000, each digit becomes 1000 times smaller, so a thousand now becomes a one. On a place value grid, we can see that the digits move 3 places to the right.
The number of zeroes in the number we are dividing by (10, 100 or 1000) reminds us how many places to move on the grid.