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Lesson plan Grade 6 Health & Consumer Science

Tanglewood PE Hydration Goals: A Grade 6 Unit-Rate Lesson

A 45-minute grade 6 health lesson where students use unit rates to turn a coach's daily water goal into bottle refills, cups, and a percent reached.

Objectives

  1. Students will convert a daily water goal in ounces into a number of bottle refills using division.
  2. Students will find what percent of a daily water goal has been reached at a point in the day.

Vocabulary

Key words: hydration, unit rate, percent, ounce

Teacher overview

Coach Ramos at Tanglewood Middle School sets a daily hydration plan for the sixth-grade physical education classes, because students who arrive at PE class already low on water tire faster and cramp more often. This lesson turns that plan into grade 6 ratio work: students take a coach's goal stated in ounces and convert it into the number of times a personal bottle needs to be refilled, the number of cups it equals, and the percent of the goal reached partway through the day. A common misconception this lesson corrects is that students can subtract to find refills; the correct move is to divide the goal by the bottle size.

All hydration goals here are the coach's own targets for a class activity, not a medical rule. The point is the ratio reasoning, so any sensible goal works. Some goals here, such as 80 and 100 ounces, are larger than most sixth graders need in a school day, so treat them as practice numbers for the math rather than amounts to drink.

Procedure

Hook (5 min): Hold up two bottles, one small and one large, and ask students to predict how many refills of each it would take to drink a full day's goal. Record a few predictions on the board without confirming them.

Direct instruction and worked example (12 min): State the situation. A student's bottle holds 20 ounces, and Coach Ramos sets a goal of 64 ounces for the school day. Model the three conversions. Refills: 64 divided by 20 equals 3.2, so the student needs to refill the bottle 4 times to reach the goal, because a partial fourth bottle is still needed. In this lesson, count every time the bottle is filled, including the first fill, as a refill. Cups: since 1 cup is 8 ounces, 64 divided by 8 equals 8 cups. Percent reached after 3 full bottles: 3 times 20 is 60 ounces, and 60 divided by 64 is about 0.94, or roughly 94 percent of the goal. Show each step as a division, and point out that the "8 ounces per cup" unit rate is what links the two ways of measuring.

Guided practice (13 min): In pairs, students solve a second case, problems 1 to 3 on the handout. The bottle holds 16 ounces and the goal is 80 ounces. They find the number of refills, the number of cups, and the percent of the goal reached after 4 full bottles. Circulate and check that pairs divide the goal by the bottle size rather than subtracting.

Independent practice (10 min): Each student completes the practice slip, problems 4 to 9 on the handout. Problems 4 to 6 use a 20-ounce bottle and a 100-ounce goal. Problems 7 to 9 use a 24-ounce bottle and a 96-ounce goal. For each bottle, students find the number of refills, the number of cups, and the percent of the goal reached after 3 full bottles.

Closure and exit ticket (5 min): Students answer problem 10, the exit ticket, on a slip: "A bottle holds 24 ounces. The goal is 72 ounces. How many refills reach the goal?" Collect and scan for students who divided correctly. If more than a few subtracted instead, reteach the division step at the start of the next class.

Tanglewood PE Hydration Goals: A Grade 6 Unit-Rate Lesson — Grade 6 Health & Consumer Science
Name: ____________________________ Date: ______________

Student Handout

Divide the goal by the bottle size to find refills, and count every time the bottle is filled, including the first fill, as a refill. Use 1 cup = 8 ounces.

Guided practice: 16-ounce bottle, 80-ounce goal

  1. How many refills of the 16-ounce bottle reach the 80-ounce goal?
  2. How many cups is the 80-ounce goal?
  3. What percent of the 80-ounce goal has the student reached after 4 full 16-ounce bottles?

Practice slip: 20-ounce bottle, 100-ounce goal

  1. How many refills of the 20-ounce bottle reach the 100-ounce goal?
  2. How many cups is the 100-ounce goal?
  3. What percent of the 100-ounce goal has the student reached after 3 full 20-ounce bottles?

Practice slip: 24-ounce bottle, 96-ounce goal

  1. How many refills of the 24-ounce bottle reach the 96-ounce goal?
  2. How many cups is the 96-ounce goal?
  3. What percent of the 96-ounce goal has the student reached after 3 full 24-ounce bottles?

Exit ticket

  1. A bottle holds 24 ounces. The goal is 72 ounces. How many refills reach the goal?

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: 5 refills. Guided practice: 80 ounces divided by 16 ounces per bottle equals exactly 5 refills.
  2. Answer: 10 cups. Guided practice: 80 ounces divided by 8 ounces per cup equals 10 cups.
  3. Answer: 80 percent. Guided practice: after 4 bottles the student has had 64 ounces, and 64 divided by 80 equals 0.80.
  4. Answer: 5 refills. Practice slip, 20-ounce bottle: 100 ounces divided by 20 ounces per bottle equals exactly 5 refills.
  5. Answer: 12.5 cups. Practice slip, 20-ounce bottle: 100 ounces divided by 8 ounces per cup equals 12.5 cups.
  6. Answer: 60 percent. Practice slip, 20-ounce bottle: after 3 bottles the student has had 60 ounces, and 60 divided by 100 equals 0.60.
  7. Answer: 4 refills. Practice slip, 24-ounce bottle: 96 ounces divided by 24 ounces per bottle equals exactly 4 refills.
  8. Answer: 12 cups. Practice slip, 24-ounce bottle: 96 ounces divided by 8 ounces per cup equals 12 cups.
  9. Answer: 75 percent. Practice slip, 24-ounce bottle: after 3 bottles the student has had 72 ounces, and 72 divided by 96 equals 0.75.
  10. Answer: 3 refills. Exit ticket: 72 ounces divided by 24 ounces per bottle equals exactly 3 refills.

Differentiation

Support

Provide a filled-in first row of a conversion table (goal, bottle size, refills, cups, percent) worked as a model, and allow a calculator for the division. Let students use physical cups and a bottle to pour and count refills before writing the numbers.

Extension

Ask students to write the general rule as an expression: if a goal is g ounces and a bottle holds b ounces, the number of refills is g divided by b, rounded up. Have them test the rule on three of their own goal-and-bottle pairs and explain when the rounded-up value matters.

ELL supports

Pre-teach "refill," "goal," and "percent" with a labeled drawing of a bottle filling and emptying. Provide sentence frames for the exit ticket, such as "The goal is ___ ounces. The bottle holds ___ ounces. It takes ___ refills."