Flat or Solid?
Aligned to K.G.A.3 — Common Core State Standards for Mathematics.
What this lesson teaches
Some shapes are flat like a drawing, and some are solid like a ball you can hold.
Worked examples
Example 1
A circle drawn on paper is flat. A ball is solid because you can pick it up and hold it.
Example 2
A square drawn on paper is flat. A box of cereal is solid — it has a front, a back, and sides you can touch.
Example 3
A flat shape lies right against the table. A solid shape sticks up off the table so you can pick it up.
Practice questions
- Is a piece of paper flat or solid?
- Find something solid you can hold in your hand.
- Point to a flat shape and a solid shape.
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
¿Plana o sólida?
Algunas figuras son planas como un dibujo, y otras son sólidas como una pelota que puedes sostener.
Ejemplo 1: Un círculo dibujado en papel es plano. Una pelota es sólida porque la puedes agarrar y sostener.
Ejemplo 2: Un cuadrado dibujado en papel es plano. Una caja de cereal es sólida — tiene frente, atrás y lados que puedes tocar.
Ejemplo 3: Una figura plana se queda pegada a la mesa. Una figura sólida sobresale de la mesa y la puedes levantar.
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