Understanding Ten Rods
Lesson 7 of 10
Objective: SWBAT represent a number using base ten blocks.
Setting Up the Learning
In this unit, students have used base 10 models before to show how to make numbers 11-19. However, this is the first time they have used this tool to show multiples of 10. This explicit discussion on the tool is aligned to MP5, use appropriate tools strategically.
This lesson also helps students develop a conceptual understanding of 10 by having students fully discuss the tool and why that tool represents 10.
Yesterday we made a number using full ten frames. Today we are going to use base ten blocks.
We use tens to help us make numbers. Ten is our best friend and we can use it to make bigger quantities! Base ten blocks are ways we show numbers in 1st, 2nd, 3rd and even 4th grade!
Your thinking job today is: How can I show a number using base ten blocks?
This lesson is aligned to CCSS Mathematical Practice standard, "Use appropriate tools strategically". It focuses heavily on what a ten rod is and how to use it appropriately in math.
I'll start the lesson by showing 10 on a ten frame.
"We have been using the ten frame to show “ten”. Today I want us to see what happens when we change that 10 into a ten stick. We call these base ten blocks."
- We will count chorally as we place blocks on top of each other. How many blocks are in this ten stick? 10! But how many tens do we have? We only have 1 stick of ten.
- If I wanted to show 20 on ten frames, how many tens would I need? How do you know?
- We need 2 full ten frames to show 20. How would we show this with base ten blocks? How many towers of 10 would I need to make 20?
A note on vocab: Calling the 10 a ten "stick" or "rod" is a scaffold I only use for the first few lessons on base 10. The Common Core asks students to use precise language when describing mathematical concepts (MP6). Using the term "ten stick" helps students understand what I am referring to, but is only a scaffold until we start to use just the term "ten".
See Student Work Time and Strategy Share.wmv for student work time and strategy share in action!
I'll use these questions to discuss the strategies I share with the class.
- If I made 30 with ten frames, how many tens would I need?
- How many towers of ten did we make?
- How could we use tens to help us count these cubes? If we counted by 1s, would we get the same amount?
- Why can we count these by 10s?
- How many tens is that? Why do we say 3 tens instead of 30 tens? What do we have 30 of? 30 tens or 30 blocks?
- When he/she counted by 10s, they said, “10, 20, 30” and then they knew it was 3 tens. How did they know it was 3 tens?
Goals for this group: I'll give these students the structure of the 10 frame to help them model making 10s there first. Then have students transfer the cubes into sticks. Push students to “prove” that each one is a ten.
Goals for this group: I'll push these students to use ten rods without the support of the ten frames.
Goals for this group: I'll push these students to answer the problems without using cubes at all to see if they can do it mentally or using a counting strategy.
See Building Tens Independent Practice.docx for independent practice sheets.
Today we showed how we could make tens out of towers and ten frames.
Partner Talk: How did you use ten towers to make the first problem?