Last year, you learned about 2-digit numbers. If you remember, a 2-digit number has 1 digit in the Tens place and 1 digit in the Ones place. In today’s lesson, we learn about place value to the Hundreds place and determine the place value of each digit in 3-digit numbers.
Math4u grade 2 first term
لشراء كتاب ماث فور يو جريد 2 أضغط هنا
ولمشاهدة شرح دروس ماث جريد 2 الترم الاول المنهج الجديد بأسلوب سهل وبسيط أضغط على الرابط التالى
ولمشاهدة شرح دروس ماث جريد 2 الترم الاول المنهج الجديد بأسلوب سهل وبسيط
أضغط على الرابط التالى
Mathematics Teacher`s Guide primary 2
Math primary 2 first term lesson 21
Learn (40 minutes)
Learn (40 minutes)
Directions
Directions
1.TEACHER DO: Write or display a place value chart with Tens and Ones. (You can use your Hundreds-Tens-Ones chart and cover up the Hundreds place.) Point to the 120 Chart.
TEACHER SAY: Raise your hand if you can find the greatest 2-digit number on our 120 Chart.
STUDENTS DO: Look at the 120 Chart. Raise hand to volunteer. Selected students share their answers.
TEACHER DO: Confirm the correct answer. Use the number cards to show 99 on the Tens-Ones chart on the board.
TEACHER SAY: Well done. This number is 99. The first 9 in the number 99 tells us there are 9 sets of Ten in 99.
TEACHER DO: Draw a line under the first 9. Tape 9 Ten strips (Base Ten manipulatives) to the board.
TEACHER SAY: The second 9 tells us there are 9 Ones.
TEACHER DO: Circle the 9 in the Ones place. Tape 9 Ones squares to the board.
TEACHER SAY: Together, we have 9 Tens and 9 Ones. That is the greatest 2-digit number. What happens when we count higher than 99? Think for a moment and then turn to your Shoulder Partner to share your thinking. Give me a Thumbs Up when you are ready to share your thinking with the group.
STUDENTS DO: Share ideas with a Shoulder Partner. Give a Thumbs Up when they are ready. Selected students share ideas with the class.
TEACHER SAY: We know that we can only have up to 9 digits in each place. We can only have up to 9 Ones in the Ones place and up to 9 Tens in the Tens place. So what happens when we add 1 to 99?
TEACHER DO: Hold up 1 Ones square and add it to the 9 Ones squares on the board.
TEACHER SAY: Can we have 10 Ones in the Ones place?
STUDENTS DO: Respond together: no.
TEACHER SAY: What do we do in Calendar Math when we get too many Ones in the Ones place? Wave at me if you know.
STUDENTS DO: Wave if they know the answer. Selected students share.
TEACHER SAY: Yes, we bundle 10 straws together and move them to the Tens place. I will do that now at the board.
TEACHER DO: Model putting 10 of the Ones squares together to form a Ten strip (or replace them with a Ten strip). Move the Ten to the Tens place.
TEACHER SAY: Great. But now we have 10 Tens in the Tens place. Can we have 10 Tens in the Tens place?
STUDENTS DO: Respond together: no.
TEACHER SAY: I am going to put 10 Tens together and move them to the next place, just as I did with the 10 Ones.
TEACHER DO: Model putting 10 of the Tens strips together to form a Hundreds block (or replace them with a Hundreds block). Move them to the next place (which is currently not labeled).
TEACHER SAY: Great, now we have put 10 Tens together to create a block of 100. I moved it to the next place. Oh no, this place does not have a name yet. What do you think it should be called? Give me a Thumbs Up if you have an idea.
STUDENTS DO: Give a Thumbs Up to volunteer. Selected students share ideas.
TEACHER DO: Confirm correct answers. If no students suggest calling the place Hundreds, explain that the next place is called Hundreds. Write Hundreds on the board above the Hundreds block.
TEACHER SAY: The place value chart helps us understand how to read this number. There are no Ones, no Tens, and 1 Hundred. This number is 100. You say 100.
STUDENTS DO: Say together: 100.
TEACHER DO: Reveal the Hundreds column on the Hundreds-Tens-Ones place value chart on the board. Use number cards to display the number 100 on the chart.
TEACHER SAY: This year, we are going to learn how to find place value in 3-digit numbers. We are going to use a Hundreds, Tens, Ones chart—or HTO chart—and Base Ten manipulatives to help us. Place value helps us understand numbers. Place value means that a digit has a specific VALUE depending on its PLACE in a number.
TEACHER DO: Hand out student sets of Base Ten manipulatives. Then, write 200, 20, and 2 on the board.
TEACHER SAY: Let’s look at more numbers. In the number 20, the place value of the 2 is 2 Tens, or 20. If the 2 were in the Ones place, its place value would be 2 Ones, or 2. If the 2 were in the Hundreds place, its place value would be 2 Hundreds, or 200. It is the same digit—2— but its value changes depending on its place in the number. Let’s all practice. Show 2 using your Base Ten manipulatives.
STUDENTS DO: Show 2 Ones squares.
TEACHER DO: Observe students as they work. Take note of students who are looking at their classmates’ work for support. (Be sure to observe each time students create a number in this lesson.) Show the correct answer at the board using your manipulatives.
TEACHER SAY: Great work. Now show 20 using your Base Ten manipulatives.
STUDENTS DO: Show 2 Tens strips.
TEACHER DO: Show correct answer at the board using your manipulatives.
TEACHER SAY: Wonderful. Now show 200.
STUDENTS DO: Show 2 Hundreds blocks.
TEACHER DO: Show correct answer at the board using your manipulatives.
TEACHER SAY: We can see that the value of the 2 changes depending on its place in the number. If the 2 is in the Ones place, its value is 2. If the 2 is in the Tens place, its value is 20. What is the value of the 2 if it is in the Hundreds place?
STUDENTS DO: Respond together: 200.
TEACHER SAY: Let’s look at another number.
TEACHER DO: Write 385 on the board (not in the HTO chart).
TEACHER SAY: Th ink about how we found the Tens and Ones in the number 99. What do you think the digits 3, 8, and 5 mean in this number? Turn and Talk to your Shoulder Partner and tell them your thoughts. Give me a Th umbs Up when you are ready to share.
STUDENTS DO: Turn and Talk to Shoulder Partner and give a Th umbs Up when they are ready. Selected students share their thinking with the class.
TEACHER SAY: Let’s put the number in the Hundreds, Tens, Ones chart on the board.
TEACHER DO: Use the number cards to show the number 385 in the HTO chart.
TEACHER SAY: In this number, we have a 3 in the Hundreds place. Th is tells us that the number 385 has 3 Hundreds.
TEACHER DO: Tape 3 Hundreds blocks under the 3. Have students show 3 Hundreds using their manipulatives.
TEACHER SAY: We are using manipulatives. If I wanted to draw 3 Hundreds, I could draw 3 big squares to represent them.
TEACHER DO: Tape 8 Tens strips onto the HTO chart. Have students show 8 Tens using their manipulatives.
TEACHER SAY: If I wanted to draw 8 Tens, I could draw 8 skinny rectangles to represent them.
TEACHER DO: Tape 5 Ones squares onto the HTO chart. Have students show 5 Ones using their manipulatives.
TEACHER SAY: If I wanted to draw 5 Ones, I could draw 5 small squares to represent them. Th e number 385 has 3 Hundreds, 8 Tens, and 5 Ones. When we read this number, we say three hundred eighty-fi ve. Say that with me.
STUDENTS DO: Say: three hundred eighty-five.
TEACHER SAY: Raise your hand if you know the place value of the 3 in this number.
STUDENTS DO: Raise hands to volunteer. Selected students answer the question: 300.
TEACHER SAY: Th e 3 is in the Hundreds place, so the place value of the 3 is 300. Raise your hand if you know the place value of the 8 in this number.
STUDENTS DO: Raise hands to volunteer. Selected students answer the question: 80.
TEACHER SAY: Th e 8 is in the Tens place, so the place value of the 8 is 80. Raise your hand if you know the place value of the 5 in this number.
STUDENTS DO: Raise hands to volunteer. Selected students answer the question: 5.
TEACHER SAY: Th e 5 is in the Ones place, so the place value of the 5 is 5. Great job.
2.TEACHER SAY: We are going to practice some more, but I need your help. Take out your student book and open it to page Lesson 21: Apply. I will use Calling Sticks to call three of you to the front. Each of you will take one number card. You will use the cards to create a 3-digit number on the Hundreds, Tens, Ones chart. Th en, you will show the number using the manipulatives. If you are sitting down, you will write the numbers in your student book and show the numbers using your manipulatives. Are you ready?
STUDENTS DO: Selected students go to the front of the room and take a number card.
TEACHER DO: Based on the three numbers the students chose, select a 3-digit number for the students to create on the chart. For example, if they chose 2, 8, and 1, you could ask them to create 821,182, or 218.
TEACHER SAY: Th e number you will create is _____. Work together to create that number in the HTO chart using your number cards and manipulatives. Remember, if you are sitting, write the 3-digit number in the Hundreds, Tens, Ones chart in your student book and use your own manipulatives to show the number. You may begin.
STUDENTS DO: Use their knowledge of place value to create the number given by the teacher (at the board or in their student book).
TEACHER SAY: Let’s check our work.
TEACHER DO: Walk through the students’ answer and point out the Hundreds, Tens, and Ones. Ask students to identify the value of each digit and add the information to the HTO chart in their student books. (Numbers will vary based on the numbers the students chose).
STUDENTS DO: Check their work. Write the value of each digit in their student book. Correct their work if necessary.
3.TEACHER SAY: Great thinking. Let’s get more of you up here to help me make our next 3-digit number.
TEACHER DO: Use Calling Sticks to select three more students. Repeat this activity two or three more times (as time allows) to give as many students a chance to participate as possible.
STUDENTS DO: Use their knowledge of place value to create the number given by the teacher (at the board or in their student book).
