8th Grade Geometry Skills
Prior Standards Implementation
The standards listed below have been replaced by a newer set of standards.
Please go to Current 8th Grade Math Standards for current resources.
Classify types of two- and three-dimensional objects using their defining properties.
- Congruent Plane Figures - draw lines of symmetry to make congruent figures
- Creating Polygons - investigating the Concept of Triangle and the Properties of Polygons ( from NCTM )
- Identify Polygons - names of polygons by number of sides and angles - instruction and review, practice, and a quiz &
- Making Triangles - investigating the Concept of Triangle and the Properties of Polygons ( from NCTM )
- Name that Polygon - identify name of given polygon components - instruction and review, practice, and a quiz &
- Polygon Playground - arrange designs with online movable polygons - hundreds of polygons to drag anywhere you want
- Triangle Identification - type of triangle, given its angles - instruction and review, practice, and a quiz &
Identify relationships among the angles (i.e., complementary, supplementary, interior, exterior, vertical, and corresponding).
- Complementary Angles - Match the angles that are complementary. (a Quia game available in Matching, Flashcards, and Concentration format)
- Geometric Terms - this Quia quiz contains four activities - matching, flash cards, concentration, and a word search puzzle - which reinforce students vocabulary concerning angles.
- Introduction to Angles - Basic terms related to the classification of angles (a Quia game available in Matching, Flashcards, Word Search, and Concentration format)
- Types of angles and pairs of angles - good illustrations
- Working with Angles - Answer the questions which deal with angles
Recognize similar geometric figures.
- Sam's Similar Shapes - learn about shapes that are different sizes but the same shape.
Determine the measure of an angle of a triangle given the measures of the other two angles.
- Angles in a Triangle - interactive applet with several examples
- Finding the Third Angle of a Triangle - instruction, practice problems and a game
- Oblique Triangles - from Dave's Short Trig Course
- Right Triangle Calculator - choose the known side then click on the calculate button
- Right Triangles - from Dave's Short Trig Course
- Sum of Angles in a Triangle - students can explore this concept by moving the vertices of the triangle with pressed mouse button
- Triangle Calculator - four different calculators
- Triangle Calculator - enter values three of the six sides and angles of the triangle and the other three values will be computed
Apply relationships among the angles and side lengths of similar geometric figures.
- A Mathematical Droodle - Two Triples of Similar Triangles
- Compass and Straightedge Construction of Similar Triangles - lesson plan from PlanetMath
- Congruent Triangles - an interactive applet
- Math Open Reference: Similar Triangles - interactive triangle lesson
- Proof Using Similar Triangles - four examples to print and use in your classroom
- Proportionality in Similar Triangles: A Cross-Cultural Comparison - a lesson plan from Convergence: a magazine of the Mathematical Association of America
- Ratio and Proportions: Similar Figures - a four part lesson including problems to work
- Similar Polygons - from Math for Morons Like Us
- Similar Triangles - a 23 slide PowerPoint show which includes scaling factors
- Similar Triangles II - a 14 slide PowerPoint show
- Similar Triangles - explanation of the concept
- Similar Triangles - a You Tube video from Mr. Vann
- Similar Triangles - includes the AA rule and the RAR rule plus two videos
- Similar Triangles and the Pythagorean theorem - from Dave's Short Trig Course
- Similar Triangles Lesson - from Oswego City School District Regents Exam Prep Center
- Similarity (geometry) - from Wikipedia
- Strategies for Dealing with Similar Triangles - from Oswego City School District Regents Exam Prep Center
- Three Similar Triangles - a math droodle
- Virtual Manipulative - Similar Triangles
Apply spatial reasoning and visualization to solve real-world problems.
- 3-D Object Viewer - Students may explore a variety of 3-D objects and their accompanying 2-D views.
- Building Houses with Side View - student constructs a block figure (dynamic, perspective drawing) to match (10 different figures)
- Coloring 3-D sides - [ UK spelling on this site ] Find the red sides shown in a series of 2-D drawings and click on the right face of the 3-D model to color it red. 20 questions
- Coloring 2-D sides - Use the colored portion of the 3-D object to color the correct side of the 2-D drawing.
- Cube - Find out which colors will be on opposite faces of a cube whose faces are shown unfolded.
- Guess the View - Students are given a 3-D view of an object, and then given a 2-D view of the object. Students must choose which of 6 views is being displayed from a list.
- Plot Plans and Silhouettes - from Shape and Space in Geometry - the student task is to come up with plot plans that could match the given silhouettes. Background information is available at another page .
- Quick Images - In the following Interactive Activity, you'll stretch both your visualization and drawing muscles. (click on Show Shape to begin the activity)
- Rotating Houses - Students are presented with a 3-D figure created with blocks that can be rotated and flipped using a mouse. The figure must be rotated until it matches a 2-D representation of one of the views.
Apply geometric ideas and relationships in areas outside the mathematics classroom (i.e., art, science, and everyday life).
Solve problems using angle relationships (i.e., complementary, supplementary, interior, exterior, vertical, and corresponding).
- Angles - practice knowledge of acute, obtuse and alternate angles.
- Classifying Angles - online quiz
- Measuring Angles - online quiz with virtual protractor
- Protractor - learn how to position and read a protractor in order to measure an angle, and how to use either scale on the protractor
- Pythagorean Theorem - online quiz
- Pythagorean Explorer - Students find the length of a side of a right triangle by using the Pythagorean Theorem, and then check their answers.
- Squaring the Triangle - Students learn about how the Pythagorean Theorem works, through investigating the standard geometric proof. Parameters: Sizes of the legs of the triangle.
- Triangle Explorer - Students learn about areas of triangles and about the Cartesian coordinate system through experimenting with triangles drawn on a grid.
National Library of Virtual Manipulatives
Geometry (Grades 6-8)
- Virginia State Standards of Learning - Select Math 8 , and then select 10, 20, or 40 questions.
- Interactive Sample Tests - released sample items from the Illinois State Board of Education
Released Tests & others
- Eighth Grade Math - Read each question and choose the best answer. Then mark the circle next to the letter for the answer you have chosen. ( from Texas )
- FCAT Sample Test Book - [ 2008 ] sample questions and test taking tips
- FCAT Sample Answer Book - [ 2008 ] sample questions and test taking tips
- TAKS 2006 Test - four subjects - math on pages 5-29
- Texas end-of-year Math test 2003
Various Review Aids
- Geometry Jeopardy - Topics covered: Polygons & Transformations, Circles, Symmetry, Lines & Angles, and Triangles & Congruency
- Illuminations - interactives for grades 6-8
- Junior High Math Interactives - includes interactive math activities, print activities, learning strategies, and videos that illustrate how math is used in everyday life.
- Math TV: Video Word Problems - [ Grades 5+ ] Math TV is a project whose goal is to help middle school students learn how to solve challenging word problems. Each of the nineteen math problems comes with step by step video solution, follow up problems, an online calculator, and sketch pad.
site for teachers | PowerPoint show | Acrobat document | Word document | whiteboard resource | sound | video format | interactive lesson | a quiz | lesson plan | to print