We also learned that if the numbers both end a 0 we can count by 10s to find the number that is halfway. count by ten starting with 850 (as students count, ask them to point to where the number would fall Let’s on the number line). It may be helpful to write the numbers on the board as students count so they can see the number that is halfway. 850, 860, 870, 880, 890, 900, 910, 920, 930, 940, 950 What number is halfway between 850 and 950? 900 If students know what comes after 890, use base ten blocks to illustrate the regrouping of 10 groups of don’t ten to make a group of a hundred. place a mark on the halfway point to remind us where 900 is located (you may write the number Let’s 900 as well). Now we can draw a line to show were the numbers belong. 3. Partner Practice Partner Practice 2, page 90: Students write 3-digit numbers in their correct location on a number line, then compare their number line with their Students should also compare and share their strategies. partner’s. Remember the focus is on number sense rather than precision. Partner Practice 2 1. Write the numbers in their correct place on the number line. 420, 590, and 510
We also learned that if the numbers both end a 0 we can count by 10s to find the number that is halfway. Let’s count by ten starting with 850 (as students count, ask them to point to where the number would fall on the number line). It may be helpful to write the numbers on the board as students count so they can see the number that is halfway. 850, 860, 870, 880, 890, 900, 910, 920, 930, 940, 950 What number is halfway between 850 and 950? 900 If students don’t know what comes after 890, use base ten blocks to illustrate the regrouping of 10 groups of ten to make a group of a hundred. Let’s place a mark on the halfway point to remind us where 900 is located (you may write the number 900 as well). Now we can draw a line to show were the numbers belong. 3. Partner Practice Partner Practice 2, page 90: Students write 3-digit numbers in their correct location on a number line, then compare their number line with their partner’s. Students should also compare and share their strategies. Remember the focus is on number sense rather than precision. Partner Practice 2 1. Write the numbers 420, 590, and 510 in their correct place on the number line.