Naming Shapes
Aligned to K.G.A.2 — Common Core State Standards for Mathematics.
What this lesson teaches
Shapes have names based on their sides and corners, no matter how big they are or which way they turn. A triangle always has 3 sides; a square has 4 equal sides.
Worked examples
Example 1
A shape with 3 straight sides and 3 corners is a triangle — even a tall skinny one or an upside-down one.
Example 2
A shape with 4 sides that are all the same length is a square. Turn it so it balances on a corner and it is still a square.
Example 3
A circle has no sides and no corners at all — that is how you know a plate is a circle and a book cover is not.
Practice questions
- Name a shape with 4 equal sides.
- How many sides does a triangle have?
- Find a circle and a rectangle in the room.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Nombrar figuras geométricas
Las figuras tienen nombres según sus lados y esquinas, sin importar qué tan grandes sean ni hacia dónde estén giradas. Un triángulo siempre tiene 3 lados; un cuadrado tiene 4 lados iguales.
Ejemplo 1: Una figura con 3 lados rectos y 3 esquinas es un triángulo, aunque sea alto y delgado o esté al revés.
Ejemplo 2: Una figura con 4 lados del mismo largo es un cuadrado. Gíralo para que se apoye en una esquina y sigue siendo un cuadrado.
Ejemplo 3: Un círculo no tiene lados ni esquinas — así sabes que un plato es un círculo y la tapa de un libro no lo es.
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