Title: Lesson 5: Using Clocks as Equivalent Fractions
Standard(s): 5.NF.A.1
Add and subtract fractions with unlike denominators (including mixed numbers) by replacing given fractions with equivalent fractions in such a way as to produce an equivalent sum or difference of fractions with like denominators. For example, 2/3 + 5/4 = 8/12 + 15/12 = 23/12 (In general, a/b + c/d = (ad + bc)/bd).
SMP#2 Reason abstractly and quantitatively.
SMP#7 Look for and make use of structure.
Lesson Overview: This lesson will review the previous days skills learned. This lesson will take the introduction of finding percentages using a 10 x 10 grid more in depth. It will focus specifically on having students find the percentages of 1/3, 2/3, 1/6, 2/6, 3/6, 4/6, and 5/6.
Resources or Materials Needed
Time: 60 Minutes
Step 1: Pre-Instructional Activities
Standard(s): 5.NF.A.1
Add and subtract fractions with unlike denominators (including mixed numbers) by replacing given fractions with equivalent fractions in such a way as to produce an equivalent sum or difference of fractions with like denominators. For example, 2/3 + 5/4 = 8/12 + 15/12 = 23/12 (In general, a/b + c/d = (ad + bc)/bd).
SMP#2 Reason abstractly and quantitatively.
SMP#7 Look for and make use of structure.
Lesson Overview: This lesson will review the previous days skills learned. This lesson will take the introduction of finding percentages using a 10 x 10 grid more in depth. It will focus specifically on having students find the percentages of 1/3, 2/3, 1/6, 2/6, 3/6, 4/6, and 5/6.
Resources or Materials Needed
- T Chart
- Blank clock template (Appedix C)
- White Boards and Markers
- Pencils
- Notebooks
- Anchor Chart Paper
- 10 x 10 grid paper
Time: 60 Minutes
Step 1: Pre-Instructional Activities
- Teacher will as students how many hours are on an analog clock.
- Teacher will explain that for the sake of these next few lessons we will only be working with 12 hours of the clock.
- Teacher will ask some students to give equivalents to certain percent’s.
- Teacher will ask students if the hour hand is the only hand we pretend is on the clock, when we get to the one we are only using what fraction of the whole 12 hour clock? 1/12
- Students will label the first hour of the clock with 1/12
- Teacher will ask the students to try the rest of these hours with their shoulder partner.
- Teacher will label the clock at each hour.
- Hour 2= 2/12=1/6
- Hour 3=3/12=1/4
- Hour 4=4/12=1/3
- Hour 5=5/12
- Hour 6=6/12=1/2
- Hour 7=7/12
- Hour 8=8/12=2/3
- Hour 9=9/12=3/4
- Hour 10=10/12=5/6
- Hour 11=11/12
- The teacher will ask students how they could add ½ + ¼= on the clock.
- Students will draw a line to hour 6 and add 3 hours to hour 6 making it hour 9=3/4. The answer to the problem should be ¾.
- Teacher will hold a small discussion how the answer came to be.
- Teacher will ask the students to complete
- 1/3 + 1/6=
- 1/4+ 1/2 =
- 1/4 + 1/3 =
- 5/12 + 1/4=
- For each problem students will use a new blank clock template
- The teacher may need to pull small groups to check for understanding.
- A pre-assessment indicated that the students do not have a very good understanding of fractions, specifically adding and subtracting fractions with like and unlike denominators
- The teacher will circulate around the room during the group time and observe student’s understanding of the content
- Students will complete a post assessment at the end of the instructional unit
- Students will be asked to complete a brief assessment at home:
- Discuss with their parents why and what they call different times of the day. I.E. Quarter to (15 minutes to the hour)
- The students will need to be prepared for a discussion about this the following day.