Lesson 7 of 13
Objective: SWBAT use efficient counting strategies to count large quantities of objects up to 100.
Setting Up the Learning
We have been working on numbers to 100. To get us started today, we are going to fill out a missing numbers hundreds chart. Reading and writing these numbers will help us as we do our activity today.
I will give the missing number hundreds chart for students to fill out as a “Do Now”; Students can partner check if time. (See attached Missing Numbers Do Now)
We are going to be using big numbers in our story problems one day so we need to get really good at counting them in order. We need to be able to understand what these numbers look like in quantity. We know how to write a 75, today we are going to look at HOW MANY 75 is.
Your thinking job today is: How can I keep track of my counting when I am counting large quantities of items?
I'll start the lesson by giving the students an interesting problem:
"While you guys were at home last night, I was trying to organize some bins of items. I wanted to figure out how many of each item I had so I could know before we use them in class. I have crayons, cheerios, pipe cleaners, blocks, cubes, dots, fuzzy counters, etc to count. I need to know how many are in each bag, so I need your help! I have this bag of crayons (at least 50 crayons). I know it is a lot of crayons but I have no idea how many!"
Partner Talk: What is your guess for how many crayons are in here? (formative data)
I'll start counting them 1 by 1 and overacts how confusing it can be by forgetting which ones I have counted so far, losing track, getting tired etc. I will keep the crayons in one big pile while counting, I want kids to identify that I should move the ones I have counted over so I can keep track more easily.
Before finishing the count, I'll say, “Wow! I am super tired out. What are the problems I am having with counting all of these one at a time?”
I will chart the responses. The problems I was faking are problems most students will encounter as they try to count a large quantity.
- You kept forgetting which ones you had counted
- They kept getting all mixed up
- You forgot what number you said.
I'll put the focus of how to count the objects correctly back on the students and say: "So now how could I figure out how many I had? I know that I kept messing up how I was counting, but I don’t know how to fix it."
Partner talk: What could I do to make counting the objects easier?
Possible student responses:
- Some students might stick to “pay closer attention”
- I'll listen for students who see that you need to separate the ones you have already counted.
- Some students may already be thinking about group counting by 10s or 5s! I'll keep those kids in mind for later.
I'll share out one idea: "I heard a group say that I need to move one over at a time. Let’s try that."
I will model counting by moving one over every time I say a number and have students whisper count along.
After the count, I'll ask: "How many crayons do we have? How do I write that number?" (I will label the bag with the number)
Partner Talk: Why was it easier to count them that time? What else could I do to make counting them easier?
At this point, I want students to not only have a strategy or two in mind for how to keep track of their counting, but I also want to give them the language for explaining their thinking in writing, a critical part of Common Core's emphasis on writing.
I will model how to read each section of the School Supply Report (see attached doc), and model how to fill out the beginning:
"I need to write down what I counted here. And write down how many there were."
Dear Ms. Cole,
I counted the crayons.
There were 75 in the bag.
When asked how they know, students will naturally say, " I know there are 75 because I counted them." I want to push them beyond that explanation by modeling how to write the strategy down.
Teacher model: "Now we need to fill out how we counted them. Now if you just tell me “I counted 75” that doesn't make me KNOW how you counted them. I want to know how you kept track of your crayons. We moved the crayons over one at a time, so I am going to write that down."
"I counted them by moving over one crayon at a time when I said the numbers. "
See attached pictures for examples of student work!
Directions: Students receive pre-made bags of objects (cheerios, crayons, pencils, counters, cubes, paper clips, erasers, etc). Students count these objects and record how many they counted on the School Supply form.
Group A (In need of intervention):
Goals: Students are able to count 1-1. These students may need hundreds chart support to help them remember what number comes next. If students are struggling just to do 1-1, I'll make the number of objects very small (less than 20) and give them ten frame support to place one cube in each ten frame spot.
Group B (Right on track):
Goals: Students count 1-1 and keep track without hundreds chart support. These students may start to group them to keep track. If I see students doing this, I'll make sure to discuss it with them. Ask:
- Why are you grouping them that way?
- How many are in your groups?
- How could we count your groups?
See attached video for a dialogue I had with one student who was specifically struggling on counting by 10s and switching to counting by 1s. I discuss this more in my reflection! Counting by 10s and 1s: A Scaffold
Group C (Extension group):
Goals: I'll pull these students and give them a separate goal. “How can you count these without have to say every single number? Is there a way you could group them to make it easier?”
Activity: Students do any of the bags up to 100, but focus in on using groupings to keep track.
Today’s thinking job was: How can I keep track of what I am counting when I am counting a big group of objects?
I saw lots of strategies for keeping track of these large quantities. Let's celebrate by doing one of our counting songs!
*Click on link to go to Dr. Jean's Macarena Count to 100 song on youtube!*