Learn exactly four (or maybe five) useful properties of parallelograms. Maybe we'll throw some area in there for good measure.

Geometry 4(A) distinguish between undefined terms, definitions, postulates, conjectures, and theorems

Geometry 5(A) investigate patterns to make conjectures about geometric relationships, including angles formed by parallel lines cut by a transversal, criteria required for triangle congruence, special segments of triangles, diagonals of quadrilaterals, interior and exterior angles of polygons, and special segments and angles of circles choosing from a variety of tools

Geometry 5(B) construct congruent segments, congruent angles, a segment bisector, an angle bisector, perpendicular lines, the perpendicular bisector of a line segment, and a line parallel to a given line through a point not on a line using a compass and a straightedge

Geometry 5(C) use the constructions of congruent segments, congruent angles, angle bisectors, and perpendicular bisectors to make conjectures about geometric relationships

Geometry 6(B) prove two triangles are congruent by applying the Side-Angle-Side, Angle-Side-Angle,Side-Side-Side, Angle-Angle-Side, and Hypotenuse-Leg congruence conditions

Geometry 11(B) determine the area of composite two-dimensional figures comprised of a combination of triangles, parallelograms, trapezoids, kites, regular polygons, or sectors of circles to solve problems using appropriate units of measure