MATHS.GCO.09.a Prove theorems about lines and angles.
Theorems include but are not limited to: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment’s endpoints.
Student Learning Targets:
Knowledge Targets
I can
I can
Reasoning Targets
I can
I can
Skills (Performance) Targets
I can
I can
Product Targets
I can
I can
Proficiency Scale
Score
Description
Sample Activity
Advanced
In addition to Score 3.0, the student demonstrates indepth inferences and applications regarding more complex material that go beyond end of instruction expectations.
Error analysis (find errors in a given proof, fix the error and explain why it was incorrect)
Concepts:
Vertical Angles
Angles created by parallel lines and a transversal
Perpendicular Bisector theorems

3.5
In addition to Score 3.0 performance, the student demonstrates indepth inferences and applications regarding the more complex content with partial success.
Proficient
“The Standard.” The student demonstrates no major errors or omissions regarding any of the information and processes that were end of instruction expectations.
Identify relevant given information
Arrange reasoning in a logical sequence
Support reasoning using appropriate justifications (theorems, postulates, definitions, etc.)
Concepts:
Vertical Angles
Angles created by parallel lines and a transversal
Perpendicular Bisector theorems
2.5
The student demonstrates no major errors or omissions regarding the simpler details and processes (Score 2.0 content) and partial knowledge of the more complex ideas and processes (Score 3.0 content).
Progressing
The student demonstrates no major errors or omissions regarding the simpler details and processes but exhibits major errors or omissions regarding the more complex ideas and processes (Score 3.0 content).
partially prove but reasoning has gaps, steps missing, incorrect reasoning, etc.
recall theorems, definitions, and postulates
fill out justification given a statement
Concepts:
Vertical Angles
Angles created by parallel lines and a transversal
Perpendicular Bisector theorems
1.5
The student demonstrates partial knowledge of the simpler details and processes (Score 2.0 content) but exhibits major errors or omissions regarding the more complex ideas and procedures (Score 3.0 content).
Beginning
With help, the student demonstrates a partial understanding of some of the simpler details and processes (Score 2.0 content) and some of the more complex ideas and processes (Score 3.0 content).

0.5
With help, the student demonstrates a partial understanding of some of the simpler details and processes (Score 2.0 content) but not the more complex ideas and processes (Score 3.0 content).
0.0
Even with help, the student demonstrates no understanding or skill.