Lesson Title: 7.NS.2d Converting Fractions to Decimals Date: _____________ Teacher(s): ____________________ Course: Common Core 7 Start/end times: _________________________ Lesson Standards/Objective(s): What mathematical skill(s) and understanding(s) will be developed? Which Mathematical Practices do you expect students to engage in during the lesson? 7.NS.2d Convert a rational number to a decimal using long division; know that the decimal form of a rational number terminates in 0s or eventually repeats. MP1: MP3: MP5: MP6: MP7: MP8: Make sense of problems and persevere in solving them. Construct viable arguments and critique the reasoning of others. Use appropriate tools strategically. Attend to precision. Look for and make use of structure. Look for and express regularity in repeated reasoning. Lesson Launch Notes: Exactly how will you use the first five minutes of the lesson? Lesson Closure Notes: Exactly what summary activity, questions, and discussion will close the lesson and connect big ideas? List the questions. Provide a foreshadowing of tomorrow. Convert the following decimals to fractions: Decimal Fraction 0.5 0.25 0.8 0.125 Solutions: Decimal Fraction 0.5 5/10 = 1/2 0.25 25/100 = ¼ 0.8 8/10 = 4/5 0.125 125/1000 = 5/40 = 1/8 Exit Ticket: Convert each fraction to a decimal. Label as terminating or repeating. Terminating or Fraction Decimal repeating 5 7 1 8 1 1 4 Solutions: Fraction 5 7 1 8 1 1 4 Decimal Terminating or repeating 0.714285 repeating 0.125 terminating 1.25 terminating Lesson Tasks, Problems, and Activities (attach resource sheets): What specific activities, investigations, problems, questions, or tasks will students be working on during the lesson? Be sure to indicate strategic connections to appropriate mathematical practices. 1. Have four student pairs go to the board to enter one of the missing fraction values. Ask each pair to explain how they obtained their answer (background knowledge, writing the decimal as a fraction using place value to determine the denominator and then simplifying, etc.). Clarify, discuss or review the skill of changing a decimal to a fraction using place value, as needed. (Look for evidence of MP6.) 2. Ask students “What is another way of representing a fraction in word form?” (¼ means the same as 1 divided by HCPSS Secondary Mathematics Office (v2.1); adapted from: Leinwand, S. (2009). Accessible mathematics: 10 instructional shifts that raise student achievement. Portsmouth, NH: Heinemann. Lesson Title: 7.NS.2d Converting Fractions to Decimals Course: Common Core 7 Date: _____________ Teacher(s): ____________________ Start/end times: _________________________ 4 and ½ is the same as 1 divided by 2). Working in pairs, have the students divide up the un-simplified and simplified fractions from the lesson launch (ex: one gets ½, 25/100, 8/10 and 1/8; the other gets 5/10, ¼, 2/5, and 125/1000). Using long division, have the students divide numerator by denominator to obtain a decimal. Have students check their results. They should be the same as the equivalent decimal in the chart. (Look for evidence of MP1 and MP6.) 3. In their notebooks, have students create a table (or continue the table from the lesson launch) with a column for fractions and a column for decimals. There are 12 fraction cards that will be converted. 4. Provide each pair of students with an envelope of the Fraction Cards. Have students take turns choosing a card from the envelope and using long division to convert to a decimal. The second student should enter the fraction into the calculator using division to check the first partner’s work. Once the decimal value is found, students should record the equivalent pair on the table in their notebook and on the back of the corresponding card. Switch rolls and repeat, until all 12 fractions have been converted. Circulate to be sure students are taking turns and that they are taking the division all the way to a terminating or repeating decimal. (Look for evidence of MP6.) 5. Once students have completed and checked all conversions, have them sort the decimal values into groups. Circulate and observe students thinking as they group the decimals. (Look for evidence of MP3 and MP7.) 6. Bring the class together. List on the board, all of the ways students sorted the decimal values, with the goal of narrowing it to the two categories of terminating and repeating decimals. Be sure to discuss the third possibility of divisors, non-terminating, non-repeating decimals (irrational numbers). Have students go back to the chart in their notebook and label each fraction/decimal pair as repeating or terminating. (Look for evidence of MP3.) 7. Discuss as a class: a. What one of two different things happened each time you converted a fraction to a decimal using division? (the divisors are always terminating or repeating decimals) b. Did you see any patterns with certain denominators? (denominators of 11 generate a repeating decimal with multiples of 9 and the numerator to form the repeating decimal pattern) (Look for evidence of MP7 and MP8.) 8. Administer the exit ticket. Evidence of Success: What exactly do I expect students to be able to do by the end of the lesson, and how will I measure student success? That is, deliberate consideration of what performances will convince you (and any outside observer) that your students have developed a deepened and conceptual understanding. The students will be able to accurately convert fractions and mixed numbers to their decimal equivalents. The students will be able to see that the division of the numerator by the denominator is complete when the decimal terminates or ends in 0s or the decimal generates a repeating pattern. The students will be able to classify the decimal form of the fraction as a terminating or a repeating decimal. Success will be measured through class discussion (#7) and completion of the exit ticket without a calculator. Notes and Nuances: Vocabulary, connections, anticipated misconceptions (and how they will be addressed), etc. Vocabulary: Dividend, divisor, terminating decimals, repeating decimals Possible misconceptions: A decimal pattern that does not repeat is not a rational number (ex: 0.1010010001); If no repeating pattern is established then it is likely there is a calculation error; A 0 in the divisor does not always indicate an end to the division problem, there must be no “remainder.” Resources: What materials or resources are essential for students to successfully complete the lesson tasks or Homework: Exactly what follow-up homework tasks, problems, and/or exercises will be assigned upon the HCPSS Secondary Mathematics Office (v2.1); adapted from: Leinwand, S. (2009). Accessible mathematics: 10 instructional shifts that raise student achievement. Portsmouth, NH: Heinemann. Lesson Title: 7.NS.2d Converting Fractions to Decimals Course: Common Core 7 Date: _____________ Teacher(s): ____________________ Start/end times: _________________________ activities? completion of the lesson? Have students choose 3 fractions with the denominator of One envelope per pair with the cut up Fraction Cards 9 and convert them to decimals using division. Write a Calculators description of any pattern that you observe. Choose a fourth fraction with a denominator of 9 and “predict” this Copies of exit ticket or slide/document to project decimal equivalent using the pattern observed. Lesson Reflections: How do you know that you were effective? What questions, connected to the lesson standards/objectives and evidence of success, will you use to reflect on the effectiveness of this lesson? Were students able to consistently recognize a fraction as a division problem? Did students find success with finding divisors that were terminating or repeating and recognizing when the division problem “ended?” Did students see the decimal patterns in the ninths and elevenths? Are there specific skills that need to be reinforced or revisited? Howard County Public Schools Office of Secondary Mathematics Curricular Projects has licensed this product under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. HCPSS Secondary Mathematics Office (v2.1); adapted from: Leinwand, S. (2009). Accessible mathematics: 10 instructional shifts that raise student achievement. Portsmouth, NH: Heinemann.