Let’s Learn!
What do I know about tens?
Goal:
Goal:
Think About It!
Goal: How can I use the tens place to add two-digit numbers?
Ariana saw so many pumpkins. We can help her by adding 10 + 10.
10
+
10
There are many ways to add 10 + 10. One way is to skip count by 10s. Skip counting is counting forward or backward by the same number. Skip counting by 10s uses whole tens: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.
These two rods show 10 + 10.
+
10
10
We can find the sum by skip counting by 10 twice. What is the sum?
10,
20
Great job! 10 + 10 = 20. Ariana saw 20 pumpkins!
We can check our work using a hundred chart. Click to see the whole tens.
Whole tens are 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.
Whole tens have a pattern. The ones place is always 0. The tens place grows by 1. We can add whole tens by jumping down the hundreds chart. The arrow on this hundreds chart shows 10 + 10.
1 ten + 1 ten = 2 tens
Our addends are 10 + 10. Start at 10. Jump down one row to add one 10.
10 + 10 = 20
How many rods do you need to show 10 + 20?
3
+
10
20
How many times do you need to skip count by 10?
Find 10 + 20 using the hundreds chart.
30
Our addends are 10 + 20. Start at 20 because it's the largest addend. Jump down one row to add 10.
10, 20, 30