Geometry Course

This is our newly revised High School Geometry Course that is aligned to the Common Core. All of the released PARCC Sample Questions are also embedded directly into the presentations. The 2014-2015 course is archived. You can get to that course by clicking this link.

Thank you to those who contribute to our ongoing cycle of improvement. Top contributors:
Suzanne Nichols-Salazar - Perth Amboy, NJ
Ruth Tocco - Haddon Heights, NJ
Angela Slaterpryce - Schroon Lake, NY

Units (select a unit)

  • Points, Lines, and Planes
    Intro to Geometry
    Points & Lines
    Congruence, Distance & Length
    Constructions & Loci
  • Angles
    Congruent Angles
    Angles & Angle Addition Postulate
    Special Angle Pairs
    Introduction to Proofs
    Proofs Special Angles
    Angle Bisectors
    Locus & Angle Constructions
    Angle Bisectors & Constructions
  • Parallel Lines
    Lines: Intersecting, Parallel & Skew
    Lines & Transversals
    Parallel Lines & Proofs
    Properties of Parallel Lines
    Constructing Parallel Lines
  • Triangles
    Triangle Sum Theorem
    Exterior Angle Theorem
    Inequalities in Triangles
    Similar Triangles
    - AA~
    - SSS~
    - SAS~
  • Similar Triangles & Trigonometry
    Problem Solving w/ Similar Triangles
    Similar Triangles & Trigonometry
    Trigonometric Ratios
    Inverse Trigonometric Ratios
    Review of the Pythagorean Theorem
    Converse of the Pythagorean Theorem
    Special Right Triangles
  • Congruent Triangles
    Congruent Triangles
    Proving Congruence: SSS
    Proving Congruence: SAS
    Proving Congruence ASA
    Proving Congruence AAS
    Proving Congruence HL
    Triangle Congruence Proofs
    Isosceles Triangle Theorem
  • Circles
    Parts of a Circle
    Central Angles & Arcs
    Arc Length & Radians
    Chords, Inscribed Angles & Triangles
    Tangents & Secants
    Segments and Circles
  • Analytic Geometry
    Origin of Analytic Geometry
    Distance Formula
    Midpoint Formula
    Partitions of a Line Segment
    Slopes of Parallel & Perpendicular Lines
    Eq of Parallel & Perpendicular Lines
    Triangle Coordinate Proofs
    Equation of a Circle & Completing the Square
  • Transformations
    Identifying Symmetry w/ Transformations
    Composition of Transformations
    Congruence Transformations
    Similarity Transformations
  • Quadrilaterals
    Properties of Parallelograms
    Proving Quads are Parallelograms
    Rhombi, Rectangles & Squares
    Constructing Quadrilaterals
    Families of Quadrilaterals
    Coordinate Proofs
  • Area of Figures
    Area of Rectangles
    Area of Triangles
    Law of Sines
    Area of Parallelograms
    Area of Regular Polygons
    Area of Circles & Sectors
    Area of Other Quadrilaterals
    Area and Perimeter of Figures in the Coordinate Plane
  • 3D Geometry
    Intro to 3-D solids
    Views & Drawings of 3-D Solids
    Surface Area of Prisms, Cylinders, Pyramids & Cones
    Volume of Prisms Prisms, Cylinders, Pyramids & Cones
    Surface Area & Volume of Spheres
    Cavalieri’s Principle
    Similar Solids
  • Probability
    Probability of Simple Events
    Probability & Length
    Probability & Area


Samuel Cerritos • 4 years, 6 months agologin to reply

I truly like the new navigation map and its tabs.-Outstanding-

Audra Crist • 4 years, 6 months agologin to reply

Dear Mr. Cerritos, Thank you for your kind words. Please do not hesitate to leave additional feedback in any of our courses. Kind regards, Audra

Deb Yoast • 3 years, 10 months agologin to reply

I like the set up of the homework problem sets! :) I was wondering, will you be doing Unit Plans for this course like the others have? Thanks!

Audra Crist • 3 years, 10 months agologin to reply

Dear Ms. Yoast, Yes, we have unit plans made in each unit. They can be found in the "Teacher Resource" category (found w/in each unit). Here is a link to the Unit Plan for the Parallel Lines Unit: Kind regards, Audra

Linda Gerdes • 3 years, 8 months agologin to reply

My class has found what we believe are errors in the homework answers. For Rotation homework, the anawer to #3c should be CD and the answer to to #CD. Also #4a and 4c are using the wrong rule. Correct answers for #4a we believe is (D(3,-2); E(-2,-4); F(-2,-7), G(2,-5); Correct answer for #4c is D(-3,2); E(2,4); F(2,7); G(-2,5). We also believe the answer to #5 is P'(-5,-1); Q'(-4,3); R'(4,2); S'(2,-3). Also #8 for the identifying symmetry with transformations. If you trace the figure and try to rotate it, it does not map onto itself.

Audra Crist • 3 years, 8 months agologin to reply

Dear Ms. Gerdes, Thank you for your comment. We will be making changes to the problems &/or answers that you mentioned within the next few business days. I'll reply again once the updated files have been posted. Kind regards, Audra

Audra Crist • 3 years, 8 months agologin to reply

Dear Ms. Gerdes, Thank you again for the comment that you left prior to the Thanksgiving holiday. The CW-HW file has been changed to reflect the corrections that you mentioned, including the re-drawing of the figures in the HW section of Identifying Symmetry with Transformations to make the answers correct. Kind regards, Audra

Lisa Shields • 3 years, 1 month agologin to reply

So what app do you recommend to open the notebook in. I want to get the correct app.

Audra Crist • 3 years, 1 month agologin to reply

Dear Ms. Shields, Thank you for your comment. Please answer the two questions below & I can provide you with more assistance: 1) What type of computer do you have? 2) What operating system does it run on? For example, a PC can run on Windows 10 & a Mac can run on OS X El Capitan. Kind regards, Audra

Alexandra Kennedy • 2 years, 11 months agologin to reply

I have the same question about running notebook, I have a Mac and can run OS X El Capitan.

Audra Crist • 2 years, 11 months agologin to reply

Dear Ms. Kennedy, Thank you for the information that you provided. SMART Notebook for Macs that run on operating systems OS X Yosemite or later does cost money, $129.00 per year (subscription), to be exact. If you are still interested, please email me directly (, and I will be happy to provide you with the download & installation information. Kind regards, Audra

Jill Jones • 2 years, 11 months agologin to reply

Do you have any resources for Proofs involving parallel lines and transversals?

Audra Crist • 2 years, 11 months agologin to reply

Dear Ms. Jones, Yes, Proofs for Parallel Lines & Transversals can be found in our Parallel Lines unit. Proofs start on slide 66 in the presentation & in the corresponding topic title in the CW-HW Word document. Kind regards, Audra

Deb Yoast • 2 years, 6 months agologin to reply

On the Circles unit on the classwork/homework, #71 seems to need some more information...or am I missing something? Thanks!

Audra Crist • 2 years, 6 months agologin to reply

Dear Deb Yoast, Thank you for your comments. When you posted your original comment last week on the Circles CW-HW file page, I was training educators in Lesotho, Africa. I found that part of the diagram for #71 was covered by the diagram in the problem directly below it. After moving the diagrams a little, I saw the missing information, redrew the diagram, for more clarity, and uploaded the CW-HW file (date stamp of 2018-01-17). Immediately after uploading the file, I wrote a reply comment to your first message on the Circles CW-HW file page, but for some reason, it didn’t show up. I’m guessing that the internet connection at the training site was not stable &/or strong enough which caused the comment to not be posted. It does happen sometimes when we’re training abroad. I apologize for not catching this issue when I tried to post my comment last week. Kind regards, Audra

Deb Yoast • 2 years, 6 months agologin to reply

No worries--thanks for getting back to me! Have a good one!

Robyn Danza • 1 year, 10 months agologin to reply

Good morning. My school district has updated to Smart Notebook 16.2. Now when I open the Smart Notebook presentations that you have, the response pages have changed. The images that you use in the questions are lost (missing) so a lot of the questions cannot be answered. Do you have a fix to this?

Melissa Axelsson • 1 year, 10 months agologin to reply

Robyn - Notebook version 16.0 is the last one that has the SMART response questions in the file the way you are used to seeing them. I would suggest you uninstall version 16.2 and then reinstall version 16.0. You can find the download for 16.0 at this link: It should jump to the section for "Senteo interactive response system". This is version 16.0 for you to download. -Melissa

Chase Tolson • 9 months, 4 weeks agologin to reply

Your content here is amazing! All of the resources are excellent, the learning progression makes so much sense and the connections between chapters are perfect. The homework, quiz, and test resources have great questions. The slides questions are so great to use in class! Thank you so much for this resource - I recommend it to all math teachers I talk to.

Susan Olszewski • 9 months, 4 weeks agologin to reply

Thank you so much for the kind words...we are so happy that you find the content useful and relevant! Thank you for helping to spread the word about our free resources.

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