Have your child count the number of sides and corners on all the shapes. Ask: How many sides does each shape have? How many corners? Say: Shapes with four straight sides and corners are called quadrilaterals.
Introduce the name of each shape: square, rectangle, trapezoid, rhombus, quadrilateral, and parallelogram. Ask questions to help your child see differences: Which quadrilaterals are slanted? Stand up straight? Which shapes have all four sides that are the same size?