Time to 15 minutes and 45 minutes - math grade 2 - lesson 59

Yesterday we practiced telling and writing time to the hour and half hour. During Reflect, we looked at a clock where the minute hand was not at the 12 or the 6. It was pointing at the 3. We shared our ideas about what time we thought that might be. In this lesson, we will learn that :15 is a quarter after the hour. we will also begin to learn how minutes are counted by 5s around the clock.

Note to the Teacher: Students have been counting by 5s during Calendar Math, so they should be able to transfer that skill to telling time. Students often want to read the time 4:15 (on an analog clock) as “4:3,” so it is important to very explicit in showing the circled times for the minutes. It also helps students to have an understanding of how long 1 minute is when they are thinking about how long 60 minutes is.

1.TEACHER DO: Draw a box on the board and label it How Many Triangles in One Minute? It should look like page Lesson 59: Apply.

TEACHER SAY: Today we are going to discuss that idea. What time is it when the minute hand is pointing to another number on our analog clock? First, we are going to talk about the minute hand a little and get an idea of how long one minute is. Who remembers how many minutes are in an hour? Tell to your Shoulder Partner.

STUDENTS DO: Tell their Shoulder Partner.

TEACHER SAY: There are 60 minutes are in one hour. Let’s see how long a minute is. Open your student book to page Lesson 59: Apply. You will see a box that is labeled How Many Triangles in One Minute? I have drawn one on the board.

STUDENTS DO: Open student book to the page for Lesson 59.

TEACHER SAY: When I say start, we will draw triangles in the box for 1 minute. When I say stop, you will stop drawing and start counting how many triangles you drew. Your triangles need to be clear and neat, so do not rush. Make sure they look like triangles with 3 straight sides. Give me a Thumbs Up if you understand the directions and are ready to go.

STUDENTS DO: Give a Thumbs Up when ready. When given the signal to start, draw triangles clearly and neatly for 1 minute. Stop when the minute is up.

TEACHER DO: Give a signal to start and keep track for 1 minute, drawing triangles in the box on the board while students are drawing triangles in the student books. Give a signal to stop.

TEACHER SAY: Wow, that was a lot of triangles. I am going to count mine. I think that since there are a lot of triangles, I will group them by 5s. I will circle each group of 5 and then I will know how many triangles I have drawn.

TEACHER DO: Model circling groups of 5 and counting by 5s (and leftover 1s) to find the total.

TEACHER SAY: Group your triangles into sets of 5. Then count how many triangles you drew in 1 minute. Write the total in your student book.

STUDENTS DO: Group triangle into sets of 5. Count triangles and record total.

TEACHER SAY: Nice job counting your triangles. I drew _____ triangles in 1 minute. That really helped me understand how long a minute is. It helps to know that when we are working with time. It takes 30 minutes for the minute hand to move to the 6 and make a half hour and 60 minutes for the minute hand to move to the 12 and make one whole hour. But what about when the minute hand only moves to the 3?

TEACHER DO: Show 4:15 on your large (or teaching) clock.

TEACHER SAY: Look at the clock in your student book.

STUDENTS DO: Look at the clock in the student book.

TEACHER DO: Point to the large clock that shows 4:15.

TEACHER SAY: The clock in your student book shows the same time as my clock. The hour hand is a little past 4 and the minute hand is on the 3. In your student book, you can see that next to each hour number there are circled numbers next to each number on the clock. Analog clocks do not usually have these, but these numbers will help us to understand how to read the minute hand. Turn to your Shoulder Partner and talk about what you notice about the numbers around the clock. Give me a Thumbs Up when you have an idea to share.

STUDENTS DO: Talk to Shoulder Partner about their observations about the numbers around the outside of the clock. Give a Thumbs Up when they are ready. Selected students share their thinking.

TEACHER SAY: Yes, these numbers count by 5s. Let’s count together as we point at each circle.

STUDENTS DO: Skip count by 5s to 60 with the teacher.

TEACHER SAY: Each of the circles that we counted is lined up with a number on the clock. Five is lined up with the 1. Ten is lined up with the 2. Fifteen is lined up with the 3, and so on. These circled numbers represent minutes and will help us think about the minutes that have passed. Under the 6, you can see a 30 for the 30 minutes that have passed when the minute hand points to the 6. Look at the number 3 on the clock. The minute hand is pointing to it. What number is in the circle outside the 3? Whisper it into your hand.

STUDENTS DO: Whisper: 15.

TEACHER SAY: Yes, there is a 15 in the circle connected to the 3. This means that the minute hand has moved to the 3, and it took 15 minutes to get there. The hour is still 4, since we remember that it will be 4 all the way until the hour hand is exactly on the 5. It is 4 the whole time the hand it is in the space between 4 and 5.

TEACHER DO: Point to this space so students can see that it stays in the 4 hour until the hand is at the 5.

Note to the Teacher: This is a challenging concept and one that needs to be modeled clearly and repeatedly. Show the students the space between the 4 and the 5. This entire space is “owned” by the 4.

TEACHER SAY: The time on this clock is 4:15.

TEACHER DO: Write the time on the board by the large clock.

TEACHER SAY: You say the time with me.

STUDENTS DO: Repeat the time with the teacher: 4:15.

TEACHER SAY: I wrote the time 4:15 on the board. The hour is 4 and the minutes are 15. The minute hand has traveled 15 minutes from 4:00. Record 4:15 under the clock in your student book.

STUDENTS DO: Record 4:15 in the student book.

TEACHER SAY: Let’s practice some more. Keep out your student book so you can see the numbers in the circles, and take out your clock. We will do as many as we can before time is up for math today.

STUDENTS DO: Take out their clock.

TEACHER SAY: I am going to say a time and you will show that time on your clock. Once you are done, compare your clock with your Shoulder Partner’s clock. Use the circles to help you think about where the minute hand should go on your clock. When you have made the time, give me a Thumbs Up.

TEACHER DO: Say a time that is to the quarter hour, such as 7:15.

STUDENTS DO: Show 7:15 on their clock. Compare work with Shoulder Partner. Give a Thumbs Up when ready. Selected students show 7:15 on the large teacher clock.

TEACHER DO: As you confirm the time, touch the 1 and say 5, the 2 and say 10, and the 3 and say 15.

TEACHER SAY: Good job. The hour hand is a little past the 7 and the minute hand is pointing at the 3, so 5, 10, 15 minutes. This clock shows 7:15.

TEACHER DO: Use Calling Sticks to select another student to write the time on the board.

STUDENTS DO: Selected student writes 7:15 on the board.

TEACHER SAY: Let’s try another one. Look at the clock in your student book and think: What will the clock look like at 5:45? Show that time on your clock, then check your work with your Shoulder Partner. When you are done, give me a Thumbs Up.

STUDENTS DO: Show 5:45 on their clock and then give a Thumbs Up. Check work with their Shoulder Partner. Give a Thumbs Up when ready. Selected students show 5:45 on the large teacher clock and write the digital time on the board.

TEACHER SAY: Nice job. At 5:45, the hour hand is past the 5 and the minute hand is at the 45. I can count by 5s around the clock. Count with me to 45 minutes.

TEACHER DO: While counting, touch each number on the class clock: Touch 1 and say 5, 2 and say 10, and so on, doing the same until you touch the 9 and say 45.

STUDENTS DO: Count along by 5s to 45.

TEACHER DO: For the rest of Learn time, repeat the process of saying a time to either :15 or :45 and have students show the time on their clock, check their work with their Shoulder Partner, and give a Thumbs Up when ready. Discuss as a group.

STUDENTS DO: Show times on clock, check work with their Shoulder Partner, and give a Thumbs Up when ready. Selected students show the time on the large teacher clock and write the digital time on the board.

Note to the Teacher: For students who are demonstrating understanding: Put them in groups of 3 to 5 to continue to practice on their own. One student says a time that is either :15 or :45. Th e other students show the analog time on their clocks and record the digital time on a sheet of paper. Th e student who said the time checks answers and all students make sure they agree. Th e students in the group rotate being the leader. For students who are struggling: Continue to work with these students, supporting them as they show times and discuss where the hour and minute hand are for :15 and :45 times.

TEACHER SAY: Great work today showing some new times where we had to read the minute hand counting by 5s. Put away your clock and turn to the Reflect section in your student book.