Comparing Solutions
Aligned to 3-5-ETS1-2 — Next Generation Science Standards.
What this lesson teaches
Most problems have more than one possible solution. Comparing ideas by your rules helps you pick the one that works best.
Worked examples
Example 1
To keep an ice cube from melting, you could wrap it in foil, cloth, or paper; testing shows which one keeps it frozen longest.
Example 2
To carry books without a bag, you could compare a strap, a box and a stack of rubber bands against how heavy a load each holds.
Example 3
Set your criteria before you test. Deciding 'cheapest' matters most after you already like one design is not a fair comparison.
Practice questions
- Think of a problem, like carrying books, and write two different solutions.
- List the rules a good solution must meet, such as being cheap or easy.
- Compare your two ideas against the rules and choose the better one.
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
Comparar soluciones
La mayoría de los problemas tienen más de una solución posible. Comparar las ideas con tus reglas te ayuda a elegir la que funciona mejor.
Ejemplo 1: Para evitar que un cubo de hielo se derrita, podrías envolverlo en papel aluminio, tela o papel; probar muestra cuál lo mantiene congelado más tiempo.
Ejemplo 2: Para cargar libros sin mochila, podrías comparar una correa, una caja y unas ligas según cuánto peso aguanta cada opción.
Ejemplo 3: Fija tus criterios antes de probar. Decidir que 'lo más barato' importa más después de que ya te gustó un diseño no es una comparación justa.
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