High School Geometry Common Core Resources
Here you will find all high school geometry resources to guide and support mathematics teaching and learning.
These resources are organized by mathematical strand and refer to specific Common Core math content standards.
Geometry: Congruence (GCO)

GCO.1
Know 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.
Problems of the Month 
GCO.2
Represent 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 (e.g., translation versus horizontal stretch).
Problems of the Month  GCO.3
 GCO.4
 GCO.5
 GCO.7
 GCO.8
 GCO.9
 GCO.10
 GCO.11
 GCO.12

GCO.13
Construct an equilateral triangle, a square, and a regular hexagon inscribed in a circle.
Problems of the Month
Geometry: Similarity, Right Triangles, and Trigonometry (GSRT)
 GSRT.1

GSRT.2
Given 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.
Performance Assessment Tasks  GSRT.5
 GSRT.6
 GSRT.7
 GSRT.8
 GSRT.11
Geometry: Circles (GC)

GC.2
Identify and describe relationships among angles, radii, and chords. Include the relationship between central, inscribed and circumscribes angles; inscribed angles on a diameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects the circle.
Problems of the MonthPerformance Assessment Tasks  GC.3