Will this help with my child's high school Geometry homework?

Yes. StudyPug covers every Geometry strand taught in Colorado high schools, including proofs, transformations, trigonometry, and coordinate geometry, so your child can find help on the exact topic assigned that night.

How long are the video lessons?

Most Geometry video lessons run between 5 and 15 minutes. They are broken into focused topics so your student can go straight to the concept they need without sitting through a full lecture.

Is there a Colorado state test for high school Geometry?

Colorado assesses math through the CMAS assessment program. High school testing focuses on specific grade levels and courses, so check with your student's school to confirm whether Geometry is a tested course this year.

Can my child use StudyPug on a tablet or phone?

Yes. StudyPug works on tablets, phones, and computers, so your student can watch lessons and complete practice problems at home, at school, or on the go.

Can I try StudyPug before paying?

Yes. StudyPug offers free sample lessons so you can explore the content before subscribing. There is also a 30-day money-back guarantee if the membership is not the right fit.

CO High School Geometry Curriculum

Give your student the support they need to keep up with Colorado Geometry. Our lessons and practice problems follow exactly what local schools teach, from congruence and similarity to circles and coordinate geometry.

CO High School Geometry Curriculum

IDStandardStudyPug Topic

CC.HSG.CO.A.1Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.
- Parallel and perpendicular line segments
- Line symmetry
- Angles in a circle
- Chord properties
- Circles and circumference
- Arcs of a circle
- Areas and sectors of circles
CC.HSG.CO.A.2Represent transformations in the plane using, e.g., transparencies and geometry software; describe transformations as functions that take points in the plane as inputs and give other points as outputs. Compare transformations that preserve distance and angle to those that do not.
- Introduction to transformations
- Rotational symmetry and transformations
CC.HSG.CO.A.3Given a rectangle, parallelogram, trapezoid, or regular polygon, describe the rotations and reflections that carry it onto itself.
- Horizontal and vertical distances
- Rectangles
- Parallelograms
- Trapezoids, rhombi, and kites
- Polygons
- Complex polygons
CC.HSG.CO.B.6Use geometric descriptions of rigid motions to transform figures and to predict the effect of a given rigid motion on a given figure; given two figures, use the definition of congruence in terms of rigid motions to decide if they are congruent.
- Congruence and congruent triangles
CC.HSG.CO.B.7Use the definition of congruence in terms of rigid motions to show that two triangles are congruent if and only if corresponding pairs of sides and corresponding pairs of angles are congruent.
- Triangles congruent by SSS proofs
CC.HSG.CO.B.8Explain how the criteria for triangle congruence (ASA, SAS, and SSS) follow from the definition of congruence in terms of rigid motions.
- Triangles congruent by SAS and HL proofs
- Triangles congruent by ASA and AAS proofs
CC.HSG.CO.C.9Prove theorems about lines and angles.
- Parallel lines and transversals
- Pairs of lines and angles
- Parallel line proofs
- Perpendicular line proofs
CC.HSG.CO.C.10Prove theorems about triangles.
- Isosceles and equilateral triangles
- Classifying triangles
- Triangles
CC.HSG.CO.C.11Prove theorems about parallelograms.
- Area and perimeter of parallelograms
CC.HSG.CO.D.12Make formal geometric constructions with a variety of tools and methods.
- Perpendicular bisectors
CC.HSG.CO.D.13Construct an equilateral triangle, a square, and a regular hexagon inscribed in a circle.
- Inscribed angles and proofs
CC.HSG.SRT.A.1Verify experimentally the properties of dilations given by a center and a scale factor.
- Enlargements and reductions with scale factors
CC.HSG.SRT.A.2Given two figures, use the definition of similarity in terms of similarity transformations to decide if they are similar; explain using similarity transformations the meaning of similarity for triangles as the equality of all corresponding pairs of angles and the proportionality of all corresponding pairs of sides.
- Similar triangles
CC.HSG.SRT.B.4Prove theorems about triangles.
- Pythagorean theorem
- Estimating square roots
- Using the pythagorean relationship
- Applications of pythagorean theorem
CC.HSG.SRT.B.5Use congruence and similarity criteria for triangles to solve problems and to prove relationships in geometric figures.
- Similar polygons
CC.HSG.SRT.C.6Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.
- Use sine ratio to calculate angles and sides (Sin = o / h)
- Use tangent ratio to calculate angles and sides (Tan = o / a)
CC.HSG.SRT.C.7Explain and use the relationship between the sine and cosine of complementary angles.
- Use cosine ratio to calculate angles and sides (Cos = a / h)
- Cofunction identities
CC.HSG.SRT.C.8Use trigonometric ratios and the Pythagorean Theorem to solve right triangles in applied problems.
- Combination of SohCahToa questions
- Word problems relating ladder in trigonometry
- Word problems relating guy wire in trigonometry
- Other word problems relating angles in trigonometry
CC.HSG.C.A.1Prove that all circles are similar.
- Central angles and proofs
CC.HSG.C.A.2Identify and describe relationships among inscribed angles, radii, and chords.
- Central and inscribed angles in circles
CC.HSG.C.A.3Construct the inscribed and circumscribed circles of a triangle, and prove properties of angles for a quadrilateral inscribed in a circle.
- Circle chord, tangent, and inscribed angles proofs
CC.HSG.C.A.4Construct a tangent line from a point outside a given circle to the circle.
- Tangent properties
CC.HSG.C.B.5Derive using similarity the fact that the length of the arc intercepted by an angle is proportional to the radius, and define the radian measure of the angle as the constant of proportionality; derive the formula for the area of a sector.
- Radian measure and arc length
- Converting between degrees and radians
- Trigonometric ratios of angles in radians
CC.HSG.GPE.A.1Derive the equation of a circle of given center and radius using the Pythagorean Theorem; complete the square to find the center and radius of a circle given by an equation.
- Conics - Circle
CC.HSG.GPE.A.2Derive the equation of a parabola given a focus and directrix.
- Conics - Parabola
CC.HSG.GPE.A.3Derive the equations of ellipses and hyperbolas given the foci, using the fact that the sum or difference of distances from the foci is constant.
- Conics - Ellipse
- Conics - Hyperbola
CC.HSG.GPE.B.4Use coordinates to prove simple geometric theorems algebraically.
- Introduction to vectors
- Slope equation: $m = \frac{y_2-y_1}{x_2- x_1}$
- Slope intercept form: y = mx + b
- General form: Ax + By + C = 0
- Point-slope form: y - y_1 = m(x - x_1)
CC.HSG.GPE.B.5Prove the slope criteria for parallel and perpendicular lines and use them to solve geometric problems.
- Parallel line equation
- Perpendicular line equation
- Combination of both parallel and perpendicular line equations
CC.HSG.GPE.B.6Find the point on a directed line segment between two given points that partitions the segment in a given ratio.
- Midpoint formula: $M = ( \frac{x_1+x_2}2 ,\frac{y_1+y_2}2)$
CC.HSG.GPE.B.7Use coordinates to compute perimeters of polygons and areas of triangles and rectangles, e.g., using the distance formula.
- Distance formula: $d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$
CC.HSG.GMD.A.1Give an informal argument for the formulas for the circumference of a circle, area of a circle, volume of a cylinder, pyramid, and cone.
- Surface area and volume of cylinders
- Surface area and volume of cones
- Surface area and volume of prisms
CC.HSG.GMD.A.3Use volume formulas for cylinders, pyramids, cones, and spheres to solve problems.
- Surface area and volume of pyramids
CC.HSG.GMD.B.4Identify the shapes of two-dimensional cross-sections of three-dimensional objects, and identify three-dimensional objects generated by rotations of two-dimensional objects.
- Surface area of 3-dimensional shapes
- Introduction to surface area of 3-dimensional shapes
- Nets of 3-dimensional shapes
CC.HSG.MG.A.1Use geometric shapes, their measures, and their properties to describe objects.
- Scale diagrams
CC.HSG.MG.A.2Apply concepts of density based on area and volume in modeling situations.
- Word problems of polynomials
CC.HSA.SSE.A.1Interpret expressions that represent a quantity in terms of its context.
- What is a polynomial?
- Applications of linear equations
CC.HSA.SSE.B.3Choose and produce an equivalent form of an expression to reveal and explain properties of the quantity represented by the expression.
- Common factors of polynomials
- Adding and subtracting rational expressions
- Evaluating polynomials
- Using algebra tiles to factor polynomials
- Solving polynomial equations
CC.HSA.CED.A.1Create equations and inequalities in one variable and use them to solve problems. Include equations arising from linear and quadratic functions, and simple rational and exponential functions.
- Introduction to linear equations
- Solving rational equations
- Solving exponential equations using exponent rules
CC.HSA.CED.A.2Create equations in two or more variables to represent relationships between quantities; graph equations on coordinate axes with labels and scales.
- Slope intercept form: y = mx + b
- Graphs of rational functions
- Applications of rational equations
- Simplifying complex fractions
- Partial fraction decomposition
CC.HSA.CED.A.3Represent constraints by equations or inequalities, and by systems of equations and/or inequalities, and interpret solutions as viable or non-viable options in a modeling context.
- Determining number of solutions to linear equations
- Linear programming word problems
- Graphing reciprocals of linear functions
- Graphing reciprocals of quadratic functions
CC.HSA.CED.A.4Rearrange formulas to highlight a quantity of interest, using the same reasoning as in solving equations.
- Point-slope form: y - y_1 = m(x - x_1)
- Graphing quadratic inequalities in two variables
- Graphing systems of quadratic inequalities
CC.HSA.REI.C.7Solve a simple system consisting of a linear equation and a quadratic equation in two variables algebraically and graphically.
- System of linear-quadratic equations
- Nature of roots of quadratic equations: The discriminant
- Applications of quadratic equations
- Solving quadratic inequalities
CC.HSF.IF.C.7Graph functions expressed symbolically and show key features of the graph, by hand in simple cases and using technology for more complicated cases.
- Graphing linear functions using a single point and slope
- Graphing quadratic functions: General form VS. Vertex form
- Graphing exponential functions
- Graphing logarithmic functions
- Graphing from slope-intercept form y=mx+b
- Graphing transformations of exponential functions
- Graphing transformations of logarithmic functions
- Sine graph: y = sin x
- Cosine graph: y = cos x
- Tangent graph: y = tan x
- Cotangent graph: y = cot x
- Secant graph: y = sec x
- Cosecant graph: y = csc x
CC.HSS.ID.B.6Represent data on two quantitative variables on a scatter plot, and describe how the variables are related.
- Reading and drawing line graphs
- Bivariate, scatter plots and correlation

Geometry

About High School Colorado Geometry

Colorado Geometry follows the Colorado Academic Standards, covering reasoning, proof, and spatial thinking across several core strands. This course works through geometric transformations and congruence, similarity and trigonometry, circles and their properties, coordinate geometry, geometric measurement and modeling, and algebraic connections to geometry. StudyPug provides video lessons and practice problems for every strand, so students can get help with exactly the topic their class is on.

Strands: transformations and congruence, similarity and trigonometry, circles, coordinate geometry, and geometric measurement and modeling
Video lessons with step-by-step explanations for every concept
Practice problems and worked examples aligned to Colorado Academic Standards
Support for proofs, constructions, applied problems, and algebraic connections

Curriculum topics by strand

Find lessons and practice problems for every strand, aligned to the Colorado Academic Standards for high school Geometry.

Topic includes:

Practice

Video

Quiz

Standard

StudyPug Topic

Colorado High School Geometry Topics

Geometric Transformations and Congruence: Rotations, reflections, translations, and rigid motions in the plane; congruence criteria including ASA, SAS, and SSS; proofs about lines, angles, triangles, and parallelograms; and formal geometric constructions.
Similarity and Trigonometry: Similarity transformations, the AA criterion, triangle similarity proofs, trigonometric ratios for acute angles, complementary angle relationships, and applying the Pythagorean Theorem to real-world problems.
Circles: Properties of inscribed angles, radii, and chords; inscribed and circumscribed circles of a triangle; tangent lines; arc length and radian measure; and area of a sector.
Coordinate Geometry: Equations of circles, parabolas, ellipses, and hyperbolas; slope criteria for parallel and perpendicular lines; partitioning directed line segments; and using coordinates to prove geometric theorems and compute perimeters and areas.
Geometric Measurement and Modeling: Volume formulas for cylinders, pyramids, cones, and spheres; cross-sections of three-dimensional objects; density applications; and using geometric methods to solve design problems.
Algebraic Connections: Creating and interpreting equations in one and two variables; systems of linear and quadratic equations; graphing functions with key features; and analyzing scatter plots for two quantitative variables.

How StudyPug Helps Colorado High School Geometry Students

When a student gets stuck on a proof or a trigonometry problem, StudyPug lets them pull up a focused video lesson on that specific concept right away. Each lesson walks through the reasoning step by step, and practice problems let the student check their understanding before the next class.

Colorado Geometry moves quickly across a wide range of topics, from transformations to coordinate proofs to volume formulas. StudyPug organizes all of these strands in one place so students can move between topics without losing their place in the course.

Aligned to Colorado High School Geometry Curriculum

Every lesson and practice problem on StudyPug is built around the Colorado Academic Standards for high school Geometry, so the content your student sees matches what their teacher is covering in class - from the precise definitions of geometric objects all the way through applying geometric methods to modeling and design problems.

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Written by the StudyPug Math Team

Last updated June 5, 2026

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