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Focus & Coherence
Gateway 1 - Meets Expectations | 77% |
|---|---|
Criterion 1.1: Focus & Coherence | 14 / 18 |
Criterion 1.1: Focus & Coherence
Focus and Coherence: The instructional materials are coherent and consistent with "the high school standards that specify the mathematics which all students should study in order to be college and career ready" (p. 57 of CCSSM).
The instructional materials reviewed for the enVision A/G/A: Algebra 1, Geometry, & Algebra 2 series meet expectations for focus and coherence. The instructional materials attend to the full intent of the mathematical content contained in the high school standards for all students, spend the majority of time on the CCSSM widely applicable as prerequisites, engage students in mathematics at a level of sophistication appropriate to high school, and make meaningful connections in a single course and throughout the series. The instructional materials partially attend to the full intent of the modeling process, let students fully learn each non-plus standard, and explicitly identify and build on knowledge from Grades 6-8.
Indicator 1a
The materials focus on the high school standards.*
Indicator 1a.i
The materials attend to the full intent of the mathematical content contained in the high school standards for all students.
The instructional materials reviewed for enVisionMath A/G/A meet expectations for attending to the full intent of the mathematical content contained in the high school standards for all students. The instructional materials include few instances where all aspects of the non-plus standards are not addressed across the series.
A few examples of non-plus standards that are fully addressed in this series include:
- N-CN.2: In Algebra 2 Lesson 2-4, students perform arithmetic operations with complex numbers as well as apply the distributive, commutative, and associative properties.
- A-REI.4b: Students solve quadratic equations by factoring in Algebra 1 lesson 9-2. Students solve quadratic equations by inspection and taking square roots in Algebra 1 lesson 9-4. In Algebra 1 lesson 9-5, students complete the square to solve quadratic equations. In Algebra 1 lesson 9-6 and Algebra 2 lesson 2-6, students solve quadratic equations using the quadratic formula.
- F-IF.6: In Algebra 1 Lessons 5-1 and 8-1, students calculate the average rate of change over a specified interval. In Algebra 2 lesson 3-1, students compare the average rate of change of a polynomial function over two different intervals.
- G-CO.4: In Geometry Lesson 3-1, students draw and describe the reflection of a figure across a line of reflection. In lesson 3-2, students describe properties of a figure before and after a translation, and in lesson 3-3, students draw and describe the rotation of a figure about a point for a given angle of reflection.
- S-ID.6a: Students use models that represent linear, quadratic, and exponential functions. In Algebra 1 lesson 3-6, students fit a linear function to data and a quadratic function to data in Algebra 2 lesson 2-2. Exponential functions are addressed in Algebra 2 lesson 6-2.
The non-plus standards that are are partially addressed in this series include:
- N-Q.1: In Algebra 1 Lesson 1-4, students use units as a way to understand problems as seen in finding average rate (miles/hour). Students also choose units consistent with formulas in example 3, as students choose inches and inches squared while calculating perimeter and area. No evidence was found where students choose and interpret the scale and the origin in graphs and data displays.
- F-LE.1a: In Algebra 1 Lesson 6-2, students identify functions as linear or exponential using tables and graphs. However, no evidence was found proving linear functions grow by equal differences, and exponential functions grow by equal factors.
- F-TF.8: In Algebra 2 Lesson 7-3, students use the Pythagorean identity to find sine, cosine, and tangent, but there is no evidence found for proving the Pythagorean identity.
- G-CO.12: In Geometry Lesson 1-2, students use a straightedge and compass to make formal geometric constructions. However, no evidence was found regarding the construction of a parallel line to a given line through a point not on the line.
- G-GMD.1: In Geometry Lesson 11-2, students use the properties of prisms and cylinders to calculate volume. No evidence was found where students make informal arguments about circumference and area of circles.
There was no evidence found in this series for A-REI.10 and G-SRT.7.
Indicator 1a.ii
The materials attend to the full intent of the modeling process when applied to the modeling standards.
The instructional materials reviewed for enVisionMath A/G/A partially meet expectations for attending to the full intent of the modeling process when applied to the modeling standards. The instructional materials omit the full intent of the modeling process for more than a few modeling standards across the courses of the series.
Each topic of the enVisionMath A/G/A series contains “Mathematical Modeling in 3 Acts” and STEM projects. In each lesson, students are posed a problem, usually by watching a video. Students develop questions of their own, formulate a conjecture, and explain how they arrived at the conjecture. In most of the tasks, the needed information is not given, and students determine what information is essential. Students compute a solution for the problem and interpret their results. Students are guided through validating their conjecture and considering reasons why their answers might differ. Students engage in the full modeling process within the “Mathematical Modeling in 3 Acts” and STEM projects. However, several modeling standards are not addressed within these 3 Acts and STEM projects.
Some of the modeling standards for which the full intent of the modeling process has been omitted include:
- N-Q.2: In Algebra 1 Lesson 1-3, there are several application problems, but none allow the student to complete the full modeling cycle. For example, on page 23 problem 50, a performance task is presented in which two individuals paint a wall. Although students determine when the painters have painted the same amount, students are not given the opportunity to create a conjecture and defend it as the rates are provided.
- A-SSE.1a: In Algebra 1 Lesson 7-5, problem 37, students use a quadratic expression to represent the area of a swimming area. Students factor the expression to determine possible dimensions of the swimming area. They interpret the factors as expressions that give the length and width of the swimming area. However, this problem does not include the full modeling cycle because students do not formulate a model, the formula is given to them. Students are not provided an opportunity to validate their results.
- A-SSE.1b: In Algebra 1 Lesson 6-3, students are shown the relationship between the growth rate and the growth factor in exponential growth. In problem 27, students determine when a particular plant will become invasive. Students are given all the necessary information and told to write an exponential growth formula. Students do not have any choice of which type of model to use, nor to identify the variables for this particular model. Students are not given the opportunity to validate their results. Other examples of parts of the modeling cycle being omitted with this modeling standard can be found in Algebra 1 Lesson 7-5, problems 37 and 41. These problems require students to compute and interpret but not formulate or validate.
- A-SSE.3a: In Algebra 1 Lesson 9-2, students solve quadratic equations by factoring. Students are given three problems (35, 36 and 39) that contain components of the modeling cycle. However in each problem, students are told to use a quadratic equation to describe the situation. In problem 35, students are given a graphical model and asked to write a quadratic equation. In problems 36 and 39, students are given a context with a diagram that is labeled with variables. Students write a quadratic equation using those variables to answer the questions. All three problems missed opportunities to have students formulate needed information and validate their findings. In Algebra 2 lesson 2-3, this topic is revisited. In problem 41, students use an equation that models the height of a drone in terms of time. This problem does not allow students to formulate a solution method because the equation is given, and students are directed how to solve the problem using the equation. Students do not validate their answer.
- A-SSE.3c: In Algebra 2 Lesson 6-2, example 1, students are shown how to use the properties of exponents to transform expressions for exponential functions; however, there are no problems where students do this as part of a modeling cycle.
- A-SSE.4: In Algebra 2 Lesson 6-7, students are shown how to derive the formula for the sum of a finite geometric series. Students use that formula to calculate a monthly payment on a loan. Students are given the formula to use and all the necessary information to solve the problem. The students compute and interpret within the problem. In problem 39 where students are not directed to use the formula for the sum of a geometric series and must formulate the correct model, then compute and interpret their result. However, the opportunity for students to validate their results is missing.
- G-GPE.7: In Geometry Lesson 9-1, students use coordinates to compute the perimeter of different polygons. In Homework problems 26-28, students use parts of the modeling process while formulating an equation and computing the perimeter of the polygon, but they are not provided the opportunity to validate their model nor interpret their results within the context of the problem.
- G-MG.2: In Geometry Lesson 11-2, problem 27, students are given information for making candles and are prompted to determine the weight of a specific order of candles. Students do not identify the needed variables as the dimensions of each candle is presented. The problem is specific and does not allow for interpreting individual findings.
- F-IF.5: In Algebra 1 Lesson 8-1, students identify key features of a quadratic function. There are several application problems for students to practice determining the average rate of change over a specific interval. Problems 26-28 provide students with aspects of the modeling process, such as evaluating a reasonable rate of change and defending that conclusion. However, students do not interpret or evaluation the solution. The questions do not provide multiple access points or various solutions.
- F-IF.6: In Algebra 2 Lesson 1-1, problem 29, students explain the meaning of the rate of change in the context of students jumping. There is only one possible solution, missing the opportunity for students to defend their solution and/or validate their conjecture.
- S-ID.6b: In Algebra 1 Lesson 3-6, students graph residuals from a linear model of data, and in lesson 8-4, students graph residuals from a quadratic model of data. Students do not complete the entire modeling process with this standard. In both lessons, students work with residuals in context, but students do not validate models or analyze results.
Examples where the materials intentionally develop the full intent of the modeling process across the series to address modeling standards include:
- In Algebra 1 Topic 2, students are presented with a situation in which height is measured in unconventional ways. Students watch a video that shows the height of a basketball player in terms of various objects. Students see a stack of cups being built next to him. As students attempt to figure out the basketball player’s height in foam cups, they have to formulate what information they would need. Data is given about smaller stacks of cups. Students utilize the information previously taught about linear functions. When students develop a plan, they complete computations. After they compute, students validate their findings when they view the final video which shows all the cups falling into place. Students report their findings compared to the final solution. This task addresses A-CED.1,3,4.
- In Algebra 2 Topic 6, students explore and apply concepts related to exponential equations and functions. Students watch a video of an athlete performing a running drill. They extrapolate both the time and distance for a certain round of the drill. Students formulate how to determine how far the athlete runs in the twentieth round and how long it will take. Students determine what information they need and consider how their ideas might relate to exponential functions. Students interpret their findings, validate them with each other, and view the final video which reveals the total time and distance. Students report their findings compared to the final solution. This task addresses F-LE.5, S-ID.6a.
- In Geometry Topic 11, students explore and apply concepts related to surface area and volume. Students are presented with different packaging options for candles. The problem is to determine the packaging option with the least surface area for a constant volume. Students watch a video which shows 24 individually-boxed candles. The smaller boxes are then packed inside one cardboard box. Students determine the dimensions of the package that has the least surface area. Students formulate a solution as they speculate how they could analyze the differences in surface area among the packages to find the one with the least surface area. Students compute a solution and think strategically to make sure they have found every possible set of dimensions for the packaging. They validate their results with each other to include ones not seen in the video. The final video shows the dimensions and surface area of each box. Students approach this solution in a variety of methods and report to each other. This task addresses G-GMD.3,4.
Indicator 1b
The materials provide students with opportunities to work with all high school standards and do not distract students with prerequisite or additional topics.
Indicator 1b.i
The materials, when used as designed, allow students to spend the majority of their time on the content from CCSSM widely applicable as prerequisites for a range of college majors, postsecondary programs, and careers.
The instructional materials reviewed for enVisionMath A/G/A meet expectations for, when used as designed, spending the majority of time on the CCSSM widely applicable as prerequisites for a range of college majors, postsecondary programs and careers (WAPs). Overall, the majority of the Algebra 1 materials address the WAPs, the majority of the Geometry materials address other non-plus standards, and the Algebra 2 materials spend less than a majority of time on the WAPs.
- In Algebra 1 the materials address the WAPs in the conceptual categories of Algebra, Functions, and Statistics and Probability. The majority of the lessons in Algebra 1 address the WAPs, and there were only a few lessons that did not include a WAP.
- In Geometry, the materials spend less than a majority of time on the WAPs, but the lessons that do not address the WAPs address other non-plus standards. Topics 1, 2, 4, 5, 7 and 8 include lessons in which the majority of the work was related to the WAPs.
- In Algebra 2 Topics 1, 2, 3 and 5 included lessons in which the majority of the work was related to the WAPs, and Topic 11 included lessons in which the majority of the work was related to non-plus standards. Topics 8, 10 and 12 of the Algebra 2 materials spend the majority of time on plus standards.
Examples of students engaging in the WAPs include:
- In Algebra 1 Topic 1, students solve linear equations and inequalities. Students solve quadratic equations in one variable in Algebra 1 Topic 9 through graphing and completing the square (A-REI.B). Students explore the structure of an expression (A-SSE.B) throughout Algebra 1 and Algebra 2, and in Algebra 2 Topic 2, students build on solving quadratics by completing the square and the quadratic formula.
- In Algebra 1 Topic 3, students determine whether a relation is a function as they explore domain and range (F-IF.A). Throughout the topic, students transform linear functions and recognize sequences as functions. In Algebra 2 Topics 1-4, students address arithmetic sequences as functions.
- In Algebra 1 Topics 3-5, students are given data with a context, calculate a trend line, and interpret the slope and y-intercept of the trend line (S-ID.7).
- In Algebra 1 Lesson 11-1, students examine center and spread of a dataset (S-ID.2), and in the next lesson, students examine the shape of a dataset. Students also examine different data sets displayed in different ways.
- In Geometry, Topics 4, 6 and 7 address triangle congruence and applying congruence and similarity of triangles to solve problems involving polygons. Students prove theorems about triangles and write a proof of the Triangle Midsegment Theorem in Geometry lesson 7-5. In lesson 8-1, students prove the Pythagorean Theorem using similarity (G-SRT.B).
- In Geometry, Topics 2, 4 and 7 address theorems about lines, angles, and triangles (G-CO.9,10). Various theorems are proven across several lessons, including the Triangle Sum Theorem in Topic 2, base angles of isosceles triangles are congruent in Topic 4, and the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length in Topic 7.
Indicator 1b.ii
The materials, when used as designed, allow students to fully learn each standard.
The instructional materials reviewed for enVisionMath A/G/A partially meet expectations for, when used as designed, letting students fully learn each non-plus standard. Overall, the series addresses many, yet not all, of the standards in a way that would allow students to fully learn the standards.
The non-plus standards that would not be fully learned by students across the series include:
- N-Q.3: In Algebra 1 Lesson 6-3, students find the population in one example. The “Common Error” box explains rounding to whole numbers when referring to people. In lesson 9-6, students round to the nearest hundredth but are given no context as to why to round to this particular number. Students are not given sufficient opportunities to practice choosing a level of accuracy when reporting quantities throughout the series.
- A-SSE.1: In Algebra 1 Lesson 7-5, students factor polynomials and interpret the factors in terms of the context; however, no opportunity exists to practice interpreting terms and coefficients in terms of the context.
- A-SSE.3c: In Algebra 1 Lesson 6-2, problems 25 and 28, students use properties of exponents to transform exponential functions. No other problems were given to help support students' learning of this standard.
- A-APR.4: In Algebra 2 Lesson 3-3, students prove the difference of cubes' identity. There is not an opportunity to prove any other identities nor use them to describe numerical relationships.
- A-REI.1: In Algebra 1 Lesson 1-2, students explain each step of solving a simple equation in an example, but there are no other opportunities for students to practice constructing a viable argument with other simple equations. In Algebra 2 lesson 5-4, students do not practice constructing arguments to justify solution methods.
- A-REI.5: In Algebra 1 Lesson 4-3, students are provided opportunities to practice solving systems of equations by elimination; however, students are not provided an opportunity to prove, given a system of two equations in two variables, replacing one equation by the sum of that equation, and a multiple of the other produces a system with the same solutions.
- F-IF.3: In Algebra 1 Lesson 1-4, example 1 shows a sequence being a function. However, there are no other opportunities found for students to recognize that sequences are functions. In addition, sequences are not defined using function notation. In Algebra 2 lesson 3-4, students determine whether each sequence is arithmetic, but students do not have the opportunity to develop a connection between sequences and functions.
- F-LE.3: In Algebra 1 Lesson 8-5, students compare linear and exponential graphs to determine which function will exceed the other in one problem. There are no other opportunities for students to address this standard.
- G-SRT.2: Geometry Lesson 7-2 addresses similarity transformations, but students do not explain similarity for triangles in terms of proportionality of all corresponding pairs of sides.
Indicator 1c
The materials require students to engage in mathematics at a level of sophistication appropriate to high school.
The instructional materials reviewed for enVisionMath A/G/A meet expectations for engaging students in mathematics at a level of sophistication appropriate to high school. The instructional materials regularly use age-appropriate contexts, use various types of real numbers, and provide opportunities for students to apply key takeaways from Grades 6-8.
Some examples where the materials illustrate age-appropriate contexts for high school students include:
- In Algebra 1 Lesson 2-2, students solve problems involving the rental of pedal boards and making payments for a cell phone.
- In Algebra 1 Lesson 4-3, students represent how many students a bus holds and the cost of the tickets as a system of equations in the context of a school field trip to an amusement park.
- In Algebra 1 Lesson 8-2, students apply the quadratic function to model the path of a volleyball in order to determine where the ball will go.
- In Geometry Lesson 2-2, students use properties of parallel lines and transversals to solve a problem involving a downhill skier maximizing their speed through a gate.
- In Geometry Lesson 5-4, students use distances on a track to find the measurements of the angles of the track.
Some examples where the materials represent key takeaways from Grades 6-8 include:
- In Algebra 1 Topic 2, students use solving linear equations to write linear equations in three different forms. Students also apply operations with rational numbers and use these properties to solve equations.
- In Algebra 1 Topic 4, students use a solving system of equations from Grade 8 to explore different methods for solving systems of equations. Students also apply their understanding of graphing linear equations in two variables to create and graph linear inequalities.
- In Algebra 1 Topic 8, students analyze graphs of functions to determine the effect of changing the values of the coefficients of quadratics and to model area and vertical motion problems.
- Geometry Topic 1 extends students’ Grade 8 learning of lines, segments, rays, and angles to learn formal definitions of the objects and use them in proofs.
- In Geometry Topic 3, students apply their understanding of congruence and similarity through rotations, reflections, translations, and dilations to learn about compositions of rigid motions.
- In Geometry Topic 7, students apply their knowledge of angle sums, exterior angles of triangles, and angle pairs formed by parallel lines cut by a transversal to learn the criteria that are sufficient to show that two triangles are similar.
- In Algebra 2 Topic 1, students apply their knowledge of solving equations from Grades 6-8 to identify key features of the graphs of linear functions.
- In Algebra 2 Topic 11, students apply their understanding of dot plots, box plots, and histograms from Grades 6-8, as well as calculate measures of center and spread, to analyze data. Students explore the requirements for a question to be considered a statistical question.
- In Algebra 2 Topic 5, students use their understanding of square roots and cube roots from Grade 8 to graph and solve radical equations. Students expand upon this skill to isolate the variable when solving radical equations.
Some examples where the instructional materials use various types of real numbers include:
- In Algebra 1 Lesson 4-2, students solve problems involving a lawn-mowing business and surfing lessons. The solutions to these problems are often decimal answers instead of whole numbers.
- In Algebra 1 Lesson 9-6, many of the problems working with the quadratic formula have irrational solutions.
- In Algebra 1 students write irrational solutions as decimal approximations. Later, in Algebra 2, students express these answers as radical expressions in simplest form. The level of sophistication increases as seen in Algebra 2 lesson 2-6, which introduces complex solutions to quadratic equations.
- In Geometry Lesson 7-3, students use decimals when determining the similarity between two triangles.
- In Geometry Lesson 8-1, students use rational and irrational numbers when finding missing sides' lengths of right triangles.
- In Algebra 2 Lesson 1-7, students have one practice problem with a decimal coefficient and another one with a rational coefficient.
- In Algebra 2 Lesson 3-5, students find the zeros of polynomial functions including integers, terminating decimals, irrational values, and imaginary numbers.
Indicator 1d
The materials are mathematically coherent and make meaningful connections in a single course and throughout the series, where appropriate and where required by the Standards.
The instructional materials reviewed for enVisionMath A/G/A meet expectations for being mathematically coherent and making meaningful connections in a single course and throughout the series, where appropriate and where required by the standards.
Some examples where the materials foster coherence through meaningful mathematical connections in a single course include:
- In Algebra 1 Topic 3, the materials introduce relations and functions (F-IF.1). The materials also develop domain and range as they relate to graphs and the quantitative relationships the graphs represent (F-IF.5). In Lessons 4 and 5, students investigate fitting functions to graphs (S-ID.6).
- In Geometry lesson 6-3, students use congruence and similarity criteria for triangles (G-SRT.5) to prove theorems about parallelograms (G-CO.11).
- In Algebra 2 Lesson 7-4, students graph and model with trigonometric functions and are introduced to terms such as amplitude, period, and midline. These terms are connected to transformations from lesson 1-2 (F-BF.3, F-TF.5).
- Algebra 2 Lesson 2-5 connects A-SSE.3b (completing the square to find the maximum or minimum) with F-IF.7a (graphing a quadratic function and show intercepts, maxima, and minima).
Some examples where the materials foster coherence through meaningful mathematical connections throughout the series include:
- In Algebra 1 Topic 3, students use function notation to express the relationship between x- and y-values as well as write, graph, and transform linear functions. In Topic 6, students continue to learn about exponential functions. In Algebra 2, students use arithmetic sequences to solve real-world problems, and in Algebra 2 Topic 6, students identify the key features of exponential functions and extend that knowledge with logarithms. (A-CED.1, A-CED.2, F-IF.7e, F-LE.4)
- In Algebra 1, students solve quadratic equations by completing the square, factoring, and using the quadratic formula. In Algebra 2, this knowledge is extended to factor higher degree polynomials and solve equations that have complex solutions. (A-SSE.3a, A-SSE.3b, A-APR.3, A-REI.4b, N-CN.7)
- In Algebra 1 Topic 10, students learn about transformations of functions, and in Algebra 2 lesson 1-2, students review these transformations. These transformations are revisited each time a new type of function is studied throughout Algebra 2. (F-BF.3)
- In Geometry Topic 8, students study trigonometric ratios of right triangles. In Algebra 2 Topic 7, students extend that knowledge to explain how the unit circle in the coordinate plane enables the extension of trigonometric functions to all real numbers, interpreted as radian measures of angles traversed counterclockwise around the unit circle (F-TF.2, G-SRT.6).
- In Geometry Topic 5, students use perpendicular bisectors, angle bisectors, medians, and altitudes to examine the relationships between the angle measures and side lengths within a triangle (G-CO.9, G-CO.10). Students also examine angle measures and side lengths of two triangles. In Algebra 2 Topic 7 examines the relationship between triangles and circles to make connections to trigonometric ratios (F-TF.1,2).
Indicator 1e
The materials explicitly identify and build on knowledge from Grades 6--8 to the High School Standards.
The instructional materials reviewed for enVisionMath A/G/A partially meet expectations for explicitly identifying and building on knowledge from Grades 6-8 to the High School CCSSM Standards. The instructional materials do not explicitly identify content from Grades 6-8.
Some examples where the materials do not explicitly identify content from Grades 6-8 include:
- At the beginning of each topic in the teacher editions, the Topic Overview Math Background Coherence standards from middle school are identified as being from Grades 6-8, but specific standards are not listed. Concepts from middle school are explicitly identified but not connected to any standard.
- The Algebra 1 Teacher Edition, page 2B states how students will use their understanding of rational and irrational numbers from Grade 8 to compare and order rational and irrational numbers in Topic 1 of Algebra 1. The materials state that students will use their understanding of solving inequalities in the form $$px + q \gt r$$ or $$px + q \lt r$$ from Grade 7 to solve compound inequalities.
- In the Geometry Teacher Edition, page 2B, informal geometric arguments from Grade 8 are referenced and connected to building formal proofs in high school, but no specific standards are identified.
Some examples where the materials make connections between Grades 6-8 and high school concepts and allow students to extend their previous knowledge include:
- Algebra 1 Teacher Edition, page 86B describes how using functions to model relationships is extended to understanding domain and range. The materials state, “In Grade 8, students began to explore linear and nonlinear functions. Students learned about the key features of linear functions, including slope and rate of change.”
- Algebra 1 Topic 8 Quadratic Functions, page 312B references, “In Grade 8, students compared linear and nonlinear functions, learned about increasing and decreasing intervals, and sketched functions from a verbal description. Students explored key features of linear functions including slope and rate of change” as a precursor to the learning of quadratics.
- Geometry Teacher Edition, page 342B references ratios and proportions and connects that to understanding trigonometric ratios (G-SRT.C). Teachers use this resource to make the connection as it is not present in the student edition.
- Geometry Teacher Edition, page 462B refers to formulas for volume of cones, cylinders, and spheres from middle school, and these are used to solve problems aligned to G-GMD involving those shapes in applications of prisms, cylinders, pyramids, cones, and spheres.
Indicator 1f
The plus (+) standards, when included, are explicitly identified and coherently support the mathematics which all students should study in order to be college and career ready.