In today's lesson, I am introducing the concept of counting by 25s as it relates to counting quarters. We are nearing the end of 1st grade, and this lesson primarily hits on a second grade standard. Although I don't expect every student to be abel to do this, I am going to expose them to the idea. If the concept is to difficult for a student, I will adapt the Race to 100 game.
I start by having the students sit in a circle on the carpet.
"During this unit we have been working on counting coins. Yesterday, I noticed that some of you started to use quarters when you were playing the Trading Game. I want to take a closer look at quarters and how we count them."
"What is one quarter worth? Yes, it is worth 25¢. When we count quarters, we count by 25s. Let's write down the counts. 25, 50, 75, 100, 125, 150, 175, 200."
I have included the Identifying 25 Count photo to show you what I wrote down.
"We will now play the game Pop and count by 25 until we get to 200."
There is a video, 25 Pop, that models this game. One student starts by saying 25, the next says 50, and it continues until they get to 200. After 200 the next student in the circle says Pop and stands up.
Advanced Preparation: You will need to make enough copies of the Race to $1.00 recording sheet for your class. Most of the kids will get through two or three sheets in today's lesson.
Before I introduce the new game to the students, I want to quickly review how to write amounts using the $ sign. Specifically, I want to reinforce that a zero has to occupy the tenths place until you get past a dime. There is a picture Notating with $ Sign, in the section resource, that captures what I write during this review. I also review that 100 cents equals $1.00. It is important for them to understand this concept.
"I want to teach you another money game called Race to 100. You will start with the recording sheet (Race to $1.00.docx). You will also need coins, a six sided die, and a pencil. You will be playing against another player and racing to 100. Each layer will need their own sheet. You will roll the die and grab that many pennies. You will then see if you can make any trades. Then you will write the coins you have on your paper and write the value. This completes your turn and then your partner goes."
"Let's play a few rounds as a class."
Note: This game can be played individually as well. I chose to work 1:1 with one student and had her play on her own.
This activity asks students to calculate the total of a set of coins (for each round), which helps students begin to understand concepts involved in the second grade standard CCSS.MATH.CONTENT.2.MD.C.8.
Students now spend time playing Race to 100.
"As you play, you should check each other's work to make sure that the trades have been made and that the coins were counted correctly."
As students work, you will want to observe the trades that students make.
The CCSS expect students to model their thinking with mathematics. In this case, they are writing amounts using the standard notation of the $ sign (CCSS.MATH.PRACTICE.MP4).
I have included a video, Playing Race to 100, in the section resource. This video captures a student playing the Race to 100 game.
I end this lesson, with a few money riddles. I call the students back to the carpet and spread out a bunch of coins in the middle of the circle.
"I am going to tell you a riddle. I want you to listen to the riddle and then try to figure out what coins I would need. I have four coins. They are worth 20 cents. What coins do I have? I want you to figure out the answer and put your thumb on your chin. I will then call on someone to share their answer."
I have included a video, Money Riddles, that models this example. I will do a few more riddles as time allows.
I will ask the students to meet me on the carpet and hand out their sheet for today's Mad Minute exercise. This routine was introduced in a previous lesson. Please check out the link to get a full overview of this routine.
I want to really focus on fact fluency and build upon the students ability to solve within ten fluently (CCSS.MATH.CONTENT.1.OA.C.6). I am going to use the Mad Minute Routine. This is a very "old school" routine, but I truly feel students need practice in performing task for fluency in a timed fashion. Students need to obtain fact fluency in order to have success with multiplicative reasoning. Students who don't gain this addition fact fluency by the end of 2nd grade tend to struggle with the multiplicative reasoning in third. Having this fluency also allows them to work on more complex tasks because the have the fact recall to focus on the higher level concepts.