Content Update: Math and AP Special Edition (July 2020)
We know our teachers might be starting to plan for the new school year, so we wanted to give an update on some upcoming course updates.
We’re excited to share that we’ve made enhancements to an AP course and 11 Math courses. See our earlier article for specific information on how much updates to each course will impact your students’ Mastery percentages.
For courses that were significantly updated, we included more information on what changed and why so you can better understand the new course content. For all courses, you'll find a list of content that was added and removed during this update.
Table of Contents
 Changes to Video Content in 2nd Grade Math
 Changes to Exercise Content in 2nd Grade Math
 Changes to Article Content in 2nd Grade Math
 Changes to Video Content in High School Geometry
 Changes to Exercise Content in High School Geometry
 Changes to Article Content in High School Geometry
 Changes to Video Content in Mathematics 1
 Changes to Exercise Content in Mathematics 1
 Changes to Article Content in Mathematics 1
 Changes to Video Content in Mathematics 2
 Changes to Exercise Content in Mathematics 2
 Changes to Exercise Content in Mathematics 2
AP Biology
Changes to Exercises Content in AP Biology
2nd Grade
The new and improved second grade course provides learners with a smooth progression through 2nd grade Common Core Standards. We added over 20 new exercises to the course to allow more depth and breadth of the standards. We also created new videos that engage the user in a quick and fun way.
 Engaging content: Our team worked hard to create items that use visuals, such as number lines, tape diagrams, base ten blocks, and ten frames to make our content more colorful and fun! We have also found ways to incorporate whimsy and even some characters you may know (like Elsa and Olaf!) in our content. Learning math may be challenging, but we also want to ensure that it is FUN!
 Aligned Instruction: We meticulously researched each standard to ensure that all standards are being appropriately addressed and assessed. As we built the course, we continuously considered the three CCSS shifts of focus, coherence, and rigor. Both the practice content and the instructional content are aligned to the CCSS.
 Conceptual Understanding: We have worked hard to put a focus on conceptual understanding throughout the course. We included scaffolded exercises, digital interactive tools, and visuals that will help solidify the conceptual piece of different standards.
 Hints: Every single practice question consists of custom hints that tackle misconceptions and make sure students understand the process to work through each individual problem. The hints were crafted to allow a “productive struggle” for students by scaffolding the solution in a way that makes sense and is age appropriate.
Changes to Video Content in 2nd Grade Math
Changes to Exercise Content in 2nd Grade Math
Changes to Article Content in 2nd Grade Math
Removed Articles 
Comparing lengths 
Measuring lengths with different units 
Algebra 1
What's changed:
 In addition to the videos and exercises below, we added 12 new skills.
 New practice focuses on concepts and their application more than procedures.
Changes to Video Content in Algebra 1
Changes to Exercise Content in Algebra 1
Algebra 2
What's changed:
 In addition to the videos and exercises below, we added 4 new skills.
 New practice focuses on concepts and their application more than procedures.
Changes to Video Content in Algebra 2
New Videos

Graph labels and scales 
Interpreting trigonometric graphs in context 
Modeling with multiple variables: Pancakes 
Modeling with multiple variables: Roller coaster 
Changes to Exercise Content in Algebra 2
New Exercises 
Graph labels and scales 
Interpreting expressions with multiple variables 
Interpreting trigonometric graphs in context 
Modeling with multiple variables 
Arithmetic
Changes to Video Content in Arithmetic
Changes to Exercise Content in Arithmetic
Basic Geometry
Changes to Video Content in Basic Geometry
New Videos 
Equal parts of circles and rectangles 
Partitioning rectangles 
Shapes and angles 
Changes to Exercise Content in Basic Geometry
New Exercises 
Analyze shapes 
Analyze shapes by angles 
Classify shapes 
Equal parts of circles 
Equal parts of rectangles 
Partitioning rectangles 
Early Math
Changes to Video Content in Early Math
Changes to Exercise Content in Early Math
High School Geometry
Here are some of the ways we're bringing the concepts of reasoning and justification—which in geometry means explaining why you are sure something is true—to the forefront and tightening our focus so students have just the right amount of support and challenge.
 Timely, targeted support: Every unit begins with an article titled "Getting ready" that reviews key prerequisite skills from earlier courses. The embedded practice in the article offers students a lowstakes and lightweight way to gauge their own readiness for the unit with links for more practice as needed. Each article empowers students to identify and revisit unfinished learning and explains how the earlier skills tie into the unit's gradelevel content.
 Proofs and justification: Throughout the course, we will complete and evaluate proofs and informal justifications. Beyond selecting proof steps and explaining why they are valid, we will also determine intermediate goals for a proof, translate between symbolic statements and what they mean verbally about figures, and identify errors in sample work.
 Conceptual depth: Geometry is about so much more than a list of formulas. We’ll explore how the building blocks of volume extend to more nuanced forms. We’ll also grapple with the relationships between angle measures and lengths, learning how one can give us clues about the other. And we’ll use the Pythagorean theorem and slope to relate visual representations of figures with their algebraic representations.
 Visual sensemaking: Are those lines definitely parallel, or could they intersect? Will the figure help us prove a property for all parallelograms or just for this particular one? We’ll sort out what's true from what's possible in diagrams and geometric constructions.
Changes to Video Content in High School Geometry
New Videos  Removed Videos 
Using right triangle ratios to approximate angle measure  Special right triangles intro (part 2) 
Using similarity to estimate ratio between side lengths  Intro to the trigonometric ratios 
Multistep word problem with Pythagorean theorem  Special right triangles intro (part 1) 
Intro to the Pythagorean trig identity  Pythagorean theorem II 
Pythagorean theorem in 3D  Intro to the Pythagorean theorem 
Dilating in 3D  Trig challenge problem: verify identities 
Cavalieri's principle in 3D  Pythagorean theorem example 
Applying volume of solids  Introduction to the Pythagorean theorem 
Volume of pyramids intuition  Intro to the Pythagorean theorem 2 
Volumes of cones intuition  Pythagorean theorem word problem: carpet 
Using related volumes  Pythagorean theorem word problem: fishing boat 
Radians as ratio of arc length to radius  Radius, diameter, circumference & π 
Calculating angle measures to verify congruence  Area of inscribed equilateral triangle 
Proving triangle congruence  Vertical angles 
Geometric constructions: perpendicular line through a point not on the line  Triangle angle challenge problem 2 
Segment congruence equivalent to having same length  Area of a quadrilateral on a grid 
Proving the SAS triangle congruence criterion using transformations  Measures of angles formed by a transversal 
Angle congruence equivalent to having same measure  Lines, line segments, & rays 
Geometric constructions: parallel line  Area of a circle 
Proving the SSS triangle congruence criterion using transformations  Area of a parallelogram 
Proving the ASA and AAS triangle congruence criteria using transformations  Measuring angles in degrees 
Geometric constructions: congruent angles  Kites as a geometric shape 
Exploring medial triangles  Sum of interior angles of a polygon 
Rational equations intro  Area of a triangle on a grid 
Proof: Parallel lines divide triangle sides proportionally  Worked example: Triangle angles (diagram) 
Equation of a parabola from focus & directrix  Area of trapezoids 
Intro to conic sections  Measuring angles using a protractor 
Intro to focus & directrix  Specifying planes in three dimensions 
Dilating triangles: find the error  Proving angles are congruent 
Dilating shapes: shrinking  Surface area using a net: rectangular prism 
Proving triangle medians intersect at a point  Worked example: Triangle angles (intersecting lines) 
Classifying figures with coordinates  Perimeter & area of composite shapes 
Radius, diameter, circumference & π  
Radius & diameter from circumference  
Measuring angles using a protractor 2  
Equation practice with complementary angles  
Quadrilateral properties  
Area of kites  
Challenge problems: perimeter & area  
Intro to nets of polyhedra  
Equation practice with supplementary angles  
Area of composite shapes  
Quadrilateral types  
Intro to quadrilateral  
Area of a triangle  
Angles, parallel lines, & transversals  
Triangle inequality theorem  
Complementary & supplementary angles  
Equation practice with vertical angles  
Acute, right, & obtuse angles  
Missing angles with a transversal  
Perimeter & area  
Parallel & perpendicular lines  
Sum of the exterior angles of a polygon  
Dilating shapes: shrinking by 1/2 
Changes to Exercise Content in High School Geometry
New Exercises  Removed Exercises 
Relate ratios in right triangles  Use Pythagorean theorem to find right triangle side lengths 
Pythagorean theorem in 3D  Use Pythagorean theorem to find isosceles triangle side lengths 
Use ratios in right triangles  Solid geometry word problems 
Apply Cavalieri's principle  Inscribed quadrilaterals 
Volume of prisms and pyramids  Vertical angles 
Apply volume of solids  Radius and diameter 
Use related volumes  Angle types 
Prove parallelogram properties  Area of a circle 
Justify triangle congruence  Surface area using nets 
Prove triangle congruence  Circumference of a circle 
Justify constructions  Area of composite shapes 
Prove triangle properties  Triangle side length rules 
Prove theorems using similarity  Shaded areas 
Rational equations intro  Equation practice with vertical angles 
Prove triangle similarity  Draw rays, lines, & line segments 
Equation of a parabola from focus & directrix  Angle relationships with parallel lines 
Classify figures by coordinates  Nets of polyhedra 
Proofs with transformations  Finding angle measures between intersecting lines 
Surface area  
Area of trapezoids  
Equation practice with angles  
Area of parallelograms  
Areas of shapes on grids  
Angles of a polygon  
Quadrilateral types  
Quadrilateral angles  
Points, lines, and planes  
Finding angle measures using triangles  
Complementary and supplementary angles (visual)  
Equation practice with angle addition  
Identify points, lines, line segments, rays, and angles  
Area of triangles  
Measure angles 
Changes to Article Content in High School Geometry
Mathematics 1
Changes to Video Content in Mathematics 1
Changes to Exercise Content in Mathematics 1
Changes to Article Content in Mathematics 1
New Articles  Removed Articles 
Getting ready for analytic geometry  Reflections review 
Getting ready for congruence  Rotations review 
Getting ready for performing transformations  Translations review 
Getting ready for transformation properties  
Properties of congruence and equality 
Mathematics 2
Changes to Video Content in Mathematics 2
Changes to Exercise Content in Mathematics 2
New Exercises  Removed Exercises 
Apply Cavalieri's principle  Inscribed quadrilaterals 
Apply volume of solids  Solid geometry word problems 
Interpret parabolas in context  Use Pythagorean theorem to find right triangle side lengths 
Interpret quadratic models  
Prove theorems using similarity  
Prove triangle similarity  
Pythagorean theorem in 3D  
Rational equations intro  
Relate ratios in right triangles  
Solve equations by completing the square  
Strategy in solving quadratics  
Use ratios in right triangles  
Use related volumes  
Volume of prisms and pyramids 
Changes to Article Content in Mathematics 2
Mathematics 3
Changes to Video Content in Mathematics 3
Changes to Exercise Content in Mathematics 3
Graph labels and scales 
Interpreting expressions with multiple variables 
Interpreting trigonometric graphs in context 
Modeling with multiple variables 
Trigonometry
Changes to Video Content in Trigonometry
New Videos 
Removed Videos

Interpreting trigonometric graphs in context 
Intro to the trigonometric ratios

Using right triangle ratios to approximate angle measure 
Trig challenge problem: verify identities

Using similarity to estimate ratio between side lengths 
Changes to Exercise Content in Trigonometry
New Exercises 
Interpreting trigonometric graphs in context 
Relate ratios in right triangles 
Unit circle 
Unit circle (with radians) 
Use ratios in right triangles 
Changes to Article Content in Trigonometry
New Articles 
Getting ready for right triangles and trigonometry 