Math Grade 6 The Number System (NS) Teacher Key Rational Numbers Part 1 Benchmarks that are Measured in this Quizlet Benchmark Code Benchmark Item # 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values 6.SMC.NS.3.1-2.b Explain the meaning of zero when using positive and negative numbers to represent quantities in real-world contexts 3, 4 6.SMC.NS.3.2-1.a Express opposite signs of numbers as indicating locations on opposite sides of 0 on the number line 5, 6 6.SMP.7.c Look for and make use of structure 1, 2, 7 7 August 2015 MATH GR6 NS QUIZLET 3 Teacher Key NOTES TO TEACHERS This series of Quizlets is meant to be used for classroom formative assessment. Different from tools to evaluate student learning summatively, they are meant to be used by teachers as a part of the instructional process. Some features of these Quizlets are: The Quizlets are fully aligned with the Benchmarks. Each Quizlet is has a variety of item types: multiple choice (MC), multiple response (MR), short response (SR) and performance-based (PB). The Quizlets were created using Microsoft® Word so that they can be modified. Item stems and graphic organizers can be used to create additional assessments that are aligned to the benchmarks. Quizlets can be used to identify benchmarks where students are struggling or identify individual students who need additional learning opportunities. Item Teacher Key: Rational Numbers Part 1 Benchmark Code Benchmark Correct Answer Number of Points 1. 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values SR 4 2. 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values SR 4 3. 6.SMC.NS.3.1-2.b Explain the meaning of zero when using positive and negative numbers to represent quantities in real-world contexts SR 2 4. 6.SMC.NS.3.1-2.b Explain the meaning of zero when using positive and negative numbers to represent quantities in real-world contexts SR 2 5. 6.SMC.NS.3.2-1.a Express opposite signs of numbers as indicating locations on opposite sides of 0 on the number line A 1 6. 6.SMC.NS.3.2-1.a Express opposite signs of numbers as indicating locations on opposite sides of 0 on the number line SR 4 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values PB 8 7. 6.SMP.7.c Look for and make use of structure Page 2 MATH GR6 NS QUIZLET 3 Teacher Key Explained Answers SHORT RESPONSE EXPLAINED ANSWERS ITEM 1. Positive and Negative on a Number Line (4 points) Benchmark: 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values Item Stem Part A Using the number line below, place an X at 3. Place another X at the point opposite of 3. Responses Points 2 points for correct response Part B What is the value of the point opposite of 3? -3 2 points for correct response SHORT RESPONSE EXPLAINED ANSWERS ITEM 2. Positive and Negative on a Number Line (4 points) Benchmark: 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values Item Stem Part A Using the number line below, plot a point 2 units to the right of 0. Plot another point 2 units to the left of zero. What is the value of each point? Responses Points 2 points for correct response Part B What is the value of each point? -2, 2 2 points for correct response SHORT RESPONSE EXPLAINED ANSWERS ITEM 3. Zero on a Number Line (2 points) Benchmark: 6.SMC.NS.3.1-2.b Explain the meaning of zero when using positive and negative numbers to represent quantities in real-world contexts Item Stem On the number line below, b = -a. What is the value of c? Responses c=0 Page 3 Points 2 points for correct response MATH GR6 NS QUIZLET 3 Teacher Key SHORT RESPONSE EXPLAINED ANSWERS ITEM 4. Fishing Boat (2 points) Benchmark: 6.SMC.NS.3.1-2.b Explain the meaning of zero when using positive and negative numbers to represent quantities in real-world contexts Item Stem Responses A boy is fishing in a boat. His fishing line is 3 feet below the surface of the water. His hat is 3 feet above the surface of the water. If the fishing line is at -3 feet and his hat is at 3 feet, what could be described as at 0 feet? The surface of the water is at 0 feet. Points 2 points for correct response SHORT RESPONSE EXPLAINED ANSWERS ITEM 6. Opposite Signs on Number Line (4 points) Benchmark: 6.SMC.NS.3.2-1.a Express opposite signs of numbers as indicating locations on opposite sides of 0 on the number line Item Stem Part A On the number line below, a = 5. What is the value of b? Responses Part B On the number line above, x = -10. What is the value of y? Page 4 Points b = -5 2 points for correct response y = 10 2 points for correct response MATH GR6 NS QUIZLET 3 Teacher Key PERFORMANCE-BASED RUBRIC ITEM 7. Tractor Pull (8 points) Benchmark: 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values Benchmark: 6 SMP.7.c Look for and make use of structure Item Stem: Level Criteria Tractors often have contests called "Tractor Pulls" (pictured below) to see which In addition to the understanding in Level 3.0, the student 4.0 tractor has the strongest engine. The tractors pull against one another until one exhibits in-depth inferences and applications that go (7-8 tractor is dragged 50 feet. Points) beyond what was taught. 3.0 (5-6 Points) Tractor A Tractor B Part A Write an "A" for Tractor A on the number line that shows the beginning of the Pull. Do the same for Tractor B. Example: 2.0 Beginning of the Tractor Pull Example (3-4 Points) Your Turn: Beginning of the Tractor Pull (assume every mark on the line equals 10 feet) 1.0 The two tractors rev their engines and begin pulling. Describe your own Tractor Pull contest in words including the beginning, middle, and end. (1-2 Points) 0.0 (0 Points) Page 5 The student exhibits no major errors or omissions at sixth grade level by: 6.SMC.NS.3.1-1.b Showing that positive and negative numbers are used together to describe quantities having opposite directions or values by showing an understanding of changing position on the number line. 6 SMP.7.c Looking for and making use of structure by showing the relationship of the changing positions on a number line. The student exhibits major errors or omissions regarding the more complex ideas and processes, but makes no major errors or omissions regarding the simpler details and processes at sixth grade level, including: 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together by changing position on the number line. 6 SMP.7.c Being unclear of the relationship of A and B on a number line. With help, the student demonstrates partial understanding of some of the score 2.0 elements and some of the score 3.0 elements at the sixth grade level. Even with help, the student demonstrates little understanding of skills. MATH GR6 NS QUIZLET 3 Teacher Key PERFORMANCE-BASED RUBRIC ITEM 7. Tractor Pull (8 points) Continued Benchmark: 6.SMC.NS.3.1-1.b Show that positive and negative numbers are used together to describe quantities having opposite directions or values Benchmark: 6 SMP 4.c Model with mathematics Item Stem: Continued Part B Place A and B on the Halfway and End lines that correspond to your description of your tractor pull contest. Half way through the Tractor Pull End of the Tractor Pull Possible Responses: Part A Write an "A" for Tractor A on the number line that shows the beginning of the Pull. Do the same for Tractor B. The two tractors rev their engines and begin pulling. Describe your own tractor pull contest in words. Description of the Tractor Pull (answers will vary) Tractors A and B begin the contest spinning their wheels. After a few minutes Tractor A starts to slowly pull Tractor B to the left 20 feet. After another few minutes of pulling, Tractor A pulls Tractor B 50 feet and wins. Beginning of the Tractor Pull Part B Place A and B on the Halfway and End lines that correspond to your description of your tractor pull contest. Half way through the Tractor Pull End of the Tractor Pull Page 6