Transformation Homework Mixed Practice is a task on transformations for geometry students. Through a series of questions, students are to construct an argument on how to get from a pre-image to an image and to critique the work of other students determining how to obtain an image. Argumentation language is used in the final question when asking students to critique work and justify their responses.

Microsoft Word version: 912Geometry_CO_Transformations_Homework_ConstructCritique_TransformationsHomework-MixedPractice

PDF version: 912Geometry_CO_Transformations_Homework_ConstructCritique_TransformationsHomework-MixedPractice


The Rotation Exploration is a task designed for geometry students learning about rotations. Students are given a conjecture about rotations claiming that the only point that stays stationary is the center of rotation. To aid in the development of an argument agreeing or disagreeing with the conjecture, students are to define vocab words, gather data, form a hypothesis, and construct an argument. Examples are given for students to gather data from and sentence starters and a checklist are provided to help with the development of a strong mathematical argument.

Microsoft Word version: 912Geometry_CO_Rotations_Worksheet_Construct_TheRotationExploration

PDF version: 912Geometry_CO_Rotations_Worksheet_Construct_TheRotationExploration


Julia’s Reflections is a task used in geometry classes when working with geometric reflections within the coordinate plane. This worksheet has students using knowledge about reflections and transformations on the coordinate grid to critique an argument about how the reflection over the line y=x transforms a figure. Students must write an argument that either agrees with or disagrees with the statement given on the worksheet.

Microsoft Word version: 912Geometry_CO_Reflections_Worksheet_ConstructCritique_JuliasReflections

PDF version: 912Geometry_CO_Reflections_Worksheet_ConstructCritique_JuliasReflections


This task was used as a performance task during our congruent triangles unit. The overall objective was for students to be able prove congruent triangles and classify triangles. This task was given towards the end of our congruent triangles unit either before or after the unit assessment. Students seemed to understand what the task was asking them to do, and the majority of students were able to answer the questions appropriately. Students did struggle on part f where they had to explain the classification of the triangle described.

Microsoft Word version: 912Geometry_CO_TriangleCongruence_Assessment_Construct_PerformanceTask-CongruentTriangles

PDF version: 912Geometry_CO_TriangleCongruence_Assessment_Construct_PerformanceTask-CongruentTriangles


This warm up is created for geometry students learning triangle congruence postulates. Students are given two problems, one with two triangles that share a side and one with two separate triangles. The questions contain argumentation language and ask students to construct an argument determining if the triangles are congruent.

Microsoft Word version: 912Geometry_CO_TriangleCongruence_Warmup_Construct_CongruencePostulates

PDF version: 912Geometry_CO_TriangleCongruence_Warmup_Construct_CongruencePostulates