Roselle School District Mathematics Curriculum Grade 8 Unit 7: Proportional Relationships, Lines, and Linear equations Essential Question(s) What is the difference between a proportional and a nonproportional relationship? How are linear relationships related to consistent rates of change? What would a graph look like for a linear relationship? How are proportions and similarity used in the real world? Enduring Understanding(s) Proportional relationships have equivalent ratios and nonproportional relationships do not have equivalent ratios. Constant rates of change when graphed will form a line just as linear relationships when graphed form a line. Proportions and similarity are often utilized in real-world situations. Summative Assessment Task See attached document Common Core Standards, 2010 Understand the connections between proportional relationships, lines, and linear equations. 8. EE.5. Graph proportional relationships, interpreting the unit rate as the slope of the graph. Compare two different proportional relationships represented in different ways. For example, compare a distance-time graph to a distance-time equation to determine which of two moving objects has greater speed. 8. EE.6. Use similar triangles to explain why the slope m is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation y = mx + b for a line intercepting the vertical axis at b. 8. F.4. Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values. 8. F.5. Describe qualitatively the functional relationship between two quantities by analyzing a graph (e.g., where the function is increasing or decreasing, linear or nonlinear). Sketch a graph that exhibits the qualitative features of a function that has been described verbally. W8.2 Write informative/explanatory texts to examine a topic and convey ideas, concepts and information through the selection, organization, and analysis of relevant content. Learning Expectations TLWBAT… Activities/Resources Student Strategies Formative Assessments Technology/Resources Find proportional relationships using a graph, interpreting the unit rate as the slope of the graph while comparing two different proportional relationships represented in two different ways: graph and equation. Introduction: Students will be given a scenario on the Smart board: “The more groceries I buy, the more money I spend,” or “The less sleep I get, the less energy I have.” Allow students to analyze if two variables are in direct variation, as one gets larger, the others get proportionally larger, or as one gets smaller, the other gets proportionally smaller. Small group instruction Introduction conducted on smart board in groups of two with white erase boards Exit ticket Mrs. Perez has $4000 in a cd and $4000 in a money market account. The amount of interest she has earned since the beginning of the year is organized in the following table (display it on page 656). Determine whether there is a direct variation between either data set and time. If so, find the equation and graph it. Video tutorial: http://www.onlinemathlea rning.com/direct-variationalgebra.html Interpret two different proportional relationships by comparing the slopes. Guided Instruction: Based on the real world scenario given, students will complete a data chart based on money spent in groceries (no money spent as well) and the number of hours a student sleeps on a nightly basis. Students will determine the direct variation (linear function) and the constant of variation. More so, they will graph the data displayed and compare ratios. Since the rate of change k is constant for any direct variation, the graph of a direct variation is always linear. Finally, the graph of any direct variation always contains the point (0,0) because for any value of k, 0 = 0 x k. Individualized instruction Independent practice Peer tutoring Allow students to work together Use of manipulatives Smart board White erase boards Choice activities Independent practice: math stations Chunking information Guided reference sheet created by Journal entry Compare and contrast proportional and nonproportional linear relationships Do now POD from LOTI Quiz Direct variation quiz created by teacher Test Battleship for advance learners: http://www.quia.com/ba/ 30197.html Independent practice: Physical science application: “When a driver applies the brakes, a car’s total stopping distance is the sum of the reaction distance and the breaking distance. The reaction distance is the distance the car travels before the drivers presses the brake pedal. The braking distance is the distance the car travels after the brakes have been applied.” Determine whether there is a direct variation between both data set and speed. If so, find the equation of the direct variation and graph it. (page 656) Use similar right triangles (rise/run) to explain why the slope is the same between any two distinct points on a non-vertical line in the coordinate plane. Compare the lines of equations with same slope but different yintercept by graphing. Find slope from a line given on a coordinate plane. Math stations to follow: taken from textbook guided practice problems on page 657. Introduction: Review of slope of a line. Allow students to complete a minute paper of 20 slope problems to determine the number of slopes each student can calculate. Students should be timed using the smart board timer or Google timer. Given a line displayed on smart board, allow students to complete the following as an introduction: Find the slope of a line What geometric figure is formed by connecting vertices (0, 2), (0,4), and (3,4)? What geometric figure is formed by connecting vertices (6,6), (6,8), and (9,8)? How do two figures identified in exercise 3 and 4 relate to each other? What geometric figure is formed by teacher Summative assessment Video tutorials from textbook Homework Handout from textbook Rephrasing of questions: What is direct variation? Describe the slope and the y-intercept of a direct variation equation. Small group instruction Introduction with class activity Individualized instruction Independent practice work displayed on class pages Peer tutoring One on one instruction with various examples Use of manipulatives Smart board White erase boards Calculators Diagrams given Exit ticket Which of the following statement is not true concerning the graph below? (display graph from pdf file) A simplified ratio of the vertical side length to the horizontal side length of each triangle is 1 Slope of the line is 1 Slope of the line is -1 Smaller triangle and larger triangle are similar Do now POD from LOTI Quiz Formative assessment on similar right triangles Cockroach game: Slope of a line interactive game:http://hotmath.com /hotmath_help/games/kp/ kp_hotmath_sound.swf Jeopardy game created by teacher. connecting the vertices (0,2), (0,6), and (6,6)? How do the two figures you identified in exercise 3 and 5 relate to each other? Triangles identified are congruent triangles. Ratio of the slope of the line of the vertical side length to the horizontal side length of each triangle. Therefore, the ratio of side length is vertical side length/horizontal side length. Independent practice: Analyze congruent triangles (examples displayed on Smart board). Challenge work: The slope of the line is -3.5. What is the simplified ratio of the vertical side length to the horizontal side length of each triangle formed? Justify your response. Construct a function to model a linear relationship between two quantities. Choice activities Display examples given for review and practice Chunking information Reference sheet given created by teacher with notes Rephrasing of questions Give steps and allow students to recite each step before completing it Working with partner Work in pairs on examples Video tutorials from textbook Small group instruction Individualized instruction Peer tutoring Use of manipulatives Computer activities for remediation Choice activities Chunking information Rephrasing of questions Working with partner Video tutorials from textbook Test Summative Assessment Oral questioning IEP recommendation Minute paper 20 slopes in one minute Directed paraphrasing Rephrasing steps needed to complete assignment Transfer and apply Steps for finding slopes of a line Homework Exit ticket Journal entry Do now Quiz Test Oral questioning Minute paper Muddiest point Directed paraphrasing One-sentence summary Transfer and apply Cubing Activities Homework Stations work Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values. Describe qualitatively the functional relationship between two quantities by analyzing a Small group instruction Individualized instruction Peer tutoring Use of manipulatives Computer activities for remediation Choice activities Chunking information Rephrasing of questions Working with partner Video tutorials from textbook Small group instruction Individualized instruction Peer tutoring Use of manipulatives Computer activities for remediation Choice activities Chunking information Rephrasing of questions Working with partner Video tutorials from textbook Small group instruction Individualized instruction Peer tutoring Use of manipulatives Computer activities for remediation Exit ticket Journal entry Do now Quiz Test Oral questioning Minute paper Muddiest point Directed paraphrasing One-sentence summary Transfer and apply Cubing Activities Homework Stations work Exit ticket Journal entry Do now Quiz Test Oral questioning Minute paper Muddiest point Directed paraphrasing One-sentence summary Transfer and apply Cubing Activities Homework Stations work Exit ticket Journal entry Do now Quiz Test Oral questioning Minute paper Muddiest point graph. Sketch a graph that exhibits the qualitative features of a function that has been described verbally Choice activities Chunking information Rephrasing of questions Working with partner Video tutorials from textbook Small group instruction Individualized instruction Peer tutoring Use of manipulatives Computer activities for remediation Choice activities Chunking information Rephrasing of questions Working with partner Video tutorials from textbook Directed paraphrasing One-sentence summary Transfer and apply Cubing Activities Homework Stations work Exit ticket Journal entry Do now Quiz Test Oral questioning Minute paper Muddiest point Directed paraphrasing One-sentence summary Transfer and apply Cubing Activities Homework Stations work