Our first few weeks of Maths in Year 3 have all been about Place value and today we used our knowledge of number lines to estimate numbers up to 1,000.
After practising finding numbers halfway between pairs of numbers, we began to apply this to number lines where the arrow points halfway between two intervals. The first thing we had to do though was to work out what the intervals on the number line represent.
The first method is to find the difference between the beginning and the end of the number line and divide that by the number of intervals. However, if we’re not feeling confident about division right now, there is another way: trial and error! We know that the intervals are going to go up in numbers that are easy to count in (e.g. 2s, 5s, 10s, 20s, 25s, 50s, 100s, etc.). So we can try different numbers out until we find one that fits!
Children volunteered to come to the front and fill out the missing numbers on the board and we were each given our own blank number line so we could all have a practice estimating given numbers.
What if there are no intervals though? When we are estimating, we learned that we always have to identify the number at the halfway point and then halfway between the beginning and this number. Then it’s easier to pin point our own number.
Once we’d had lots of practice on our whiteboards and sheets and we were feeling nice and confident, it was time to put our knowledge to the test by answering the questions in our White Rose Maths workbooks. Next we’ll be comparing and ordering numbers and it won’t be long before we begin our next topic, addition and subtraction!
