6th Grade · Week 1 of 36 · Math

Ratios as comparisons; tape diagrams (CPA)

Learning goal By the end of this lesson you can: understand a ratio as a comparison of two quantities and model ratios with tape diagrams.

1. Hook

How to do this lesson online
  1. Read (or listen to) what you’re learning. Don’t jump to the quiz.
  2. Walk the worked example. Then use the interactive lab on this page.
  3. Guided set → independent set → mastery check → teach-back.
  4. If you write a paper, stay on campus: Citation Helper, Source Library, Paper Studio.

This is self-paced homeschool on Life Academy. Everything you need is on this page.

Today's puzzle

A trail mix has 3 cups of nuts for every 2 cups of raisins. If you see only the bag, how could you draw what "3 to 2" means?

Then: lab → guided → quiz → teach it back. The lab is the lesson, not a decoration.

2. Teach

What you're learning

Understand a ratio as a comparison of two quantities and model ratios with tape diagrams (CCSS 6.RP.A.1).

Standards alignment: CCSS.MATH.CONTENT.6.RP (domain-level; works with any state’s standards)

STEM in this lesson

Engineers mix concrete by ratio (for example 1 part cement : 2 parts sand : 3 parts gravel). A tape diagram shows the parts so you can scale a batch without changing the mix.

Hold onto these
  • A ratio compares two quantities: 3 to 2, 3:2, or 3/2.
  • Order matters: nuts to raisins 3:2 is not raisins to nuts 2:3.
  • A tape diagram uses equal-sized boxes, one box per unit of the ratio.
This week’s lesson

Concrete: put out 3 red blocks and 2 blue blocks. Pictorial: draw 3 boxes labeled N and 2 boxes labeled R, all the same size. Abstract: write N:R = 3:2.

Ratios can be part-to-part (nuts to raisins 3:2) or part-to-whole (nuts to all mix 3:5), because 3 + 2 = 5 boxes in all.

Watch one worked example
  1. Problem: nuts to raisins is 3:2 and the bag holds 20 cups total.
  2. Draw 3 + 2 = 5 equal boxes.
  3. 20 cups ÷ 5 boxes = 4 cups per box.
  4. Nuts = 3 × 4 = 12 cups; raisins = 2 × 4 = 8 cups. Check: 12 + 8 = 20.
Now you try — with me

A class has 4 boys for every 5 girls and 27 students. Draw a tape diagram and find the number of girls.

The usual mistake

Reversing the order of the ratio, or dividing the total by one part instead of by the total number of boxes.

Why this shows up in real life

Recipes, paint mixes, and sports records (wins to losses) are all ratios.

No classroom teacher today — this page is the lesson. Follow the how-to, then the lab, then the quiz. Follow Lesson Studio, then the lab, then the quiz.

Open Lesson Studio (Week 1) →

Interactive lab (on this page)

Change one variable. Record what happened. This model is the lab — not an off-site sim.

Your work — type it here

Type the answer. Then tap Check my work. This is the assignment — not optional reading.

3. Guided practice

Try these with me — type the missing word, then check.

Reveal the thinking

Count the boxes, divide the total by the number of boxes, then multiply by each part.

4. Independent practice

Work the set. Check when finished — this is practice (mastery quiz is next).

1. 6 apples and 4 pears. Apples to pears
2. A tape diagram uses boxes that are
3. 2:5 with total 35. The larger part
4. Part-to-whole for 3:4 (first part)

5. Mastery check

Scored quiz — results save to your gradebook.

1. 8 wins and 2 losses. Wins to losses in simplest form
2. 1:1 ratio with 18 total. Each part
3. Which equals the ratio 3 to 5
4. 5 boxes represent 40. One box

Show the math — don't only tap a letter

The lab is the worked example you can move. Then the quiz checks that you own Ratios as comparisons; tape diagrams (CPA).

Classroom · Gradebook · Transcripts

Stay on this page. The studio, the lab, pictures, and Your work are the lesson.

6. Reflection / teach-back

Teach-back: Explain Ratios as comparisons; tape diagrams (CPA) in your own words. Give one example and name the usual mistake.

Teacher notes (optional) — adult coaching script for Week 1