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Unit 1: Number System Launch Lesson 1-1 6.NOS.4

Prime Factorization

I can write a number as a product of its prime factors using a factor tree.

Speaking and writing goal: I can explain how I broke a number down using the words prime number, composite number, factor, and exponent.

What Your Child Is Learning

In this lesson, students practice how to write a number as a product of its prime factors using a factor tree. They learn to show their thinking with numbers, pictures, words, or a model. The goal is not just getting an answer. Students should be able to explain why the answer makes sense.

Why This Matters

This skill supports everyday problem solving with money, measurements, games, planning, and checking whether an answer is reasonable.

What It May Look Like In Class

Your child may use the interactive lesson, guided notes, examples from the board, partner talk, and short practice problems. They may be asked to solve, draw a model, label important numbers, and explain their reasoning in a sentence.

How You Can Help At Home

You do not need to teach a new method. Ask your child to read the problem out loud, circle the important numbers, and explain what they tried first. Helpful questions include: What do you know? What are you trying to find? Does your answer make sense?

Apoyo para familias en español

Qué está aprendiendo su hijo/a

En esta lección, su hijo/a practica usar números con cuidado y explicar sus pasos. Puede usar dibujos, números, palabras o modelos para mostrar su pensamiento. Lo más importante es que pueda explicar por qué su respuesta tiene sentido.

Por qué es importante

Esta habilidad ayuda con dinero, medidas, juegos, planificación y con revisar si una respuesta es razonable.

Cómo puede ayudar en casa

No necesita ser experto/a en matemáticas. Pídale a su hijo/a que lea el problema en voz alta, marque los números importantes y explique su primer paso. Puede preguntar: ¿Qué sabes? ¿Qué necesitas encontrar? ¿Tu respuesta tiene sentido?

Key Vocabulary

Prime number Número primo

A number bigger than 1 that you can only divide by 1 and itself.

Example: 7

Composite number Número compuesto

A number bigger than 1 that you can divide by more than just 1 and itself.

Example: 12

Prime factorization Factorización prima

Writing a number as prime numbers multiplied together.

Factor Factor

A factor of a whole number divides it evenly, with no remainder. For example, 3 is a factor of 12 because 12 ÷ 3 = 4.

Example: 3 is a factor of 12

Factor tree Árbol de factores

A picture that splits a number into its prime numbers, step by step.

Exponent Exponente

A small number that tells how many times to multiply a number by itself.

Example: The 3 in 2³

Try It Together

Pick one or two problems. Let your child explain the first step before opening the answer.

  1. Make a factor tree for 36.
    Show answer

    36 = 2 x 2 x 3 x 3

  2. List all factors of 24.
    Show answer

    1, 2, 3, 4, 6, 8, 12, 24

  3. Is 29 prime or composite? How do you know?
    Show answer

    Prime; only 1 and 29 divide it evenly.

  4. What is the greatest common factor of 18 and 30?
    Show answer

    6