Once your fifth grader has mastered the basics, it's time to start finding the surface areas of 3-D shapes--like cubes.

Your child will need to use their triangle knowledge to find the area of the sails on this sailboat.

Practice finding the area of many different parallelograms with this one-page geometry worksheet!

Take your child's geometry practice to the seas! Can your child use his triangle knowledge to find the area of the sail on this sailboat?