Back to the lesson plan builder
Lesson length30 min45 min60 min
Questions🔀 New questions

Print the plan for yourself; the student sheet prints on its own page after it.

Science lesson plan · 7th grade (Year 8 in England) · 30 minutes

Test foods for starch, sugar, protein and fat

Human body and health

CCSS NGSS.MS-LS1-7CCSS NGSS.SEP 3England: KS3 Biology: Nutrition and digestionEngland: GCSE Combined Science: Organisation (required practical: food tests)

Objective and success criteria

Students will: Test foods for starch, sugar, protein and fat.

  • I can answer questions on today's skill on my own, without help.
  • I can explain each step and say why it works.
  • I can check my answer and spot a mistake.

Before and after

Needs first: Food groups, nutrients and what each one does

Leads to: the next skill in this area.

Materials: Stopwatches, Body diagrams, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).

Warm-up · 4 min

  • Quick retrieval from earlier learning (Food groups, nutrients and what each one does). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. Which nutrient group matches this: needed for growth and repair of cells? (lipids (fats and oils) / carbohydrates / proteins / vitamins and minerals) → proteinsPrompt: Energy, growth, stored energy, small amounts for health, or keeping the gut moving?
  2. A portion of noodles contains 36 g of carbohydrate, 11 g of protein and 14 g of fat. Carbohydrate and protein each release 17 kJ per gram; fat releases 37 kJ per gram. How much energy does it provide, in kJ? → 1317 kJPrompt: Work out the energy from each nutrient separately.
  3. A teenager eats lots of white bread and sweets but few vegetables, and has constipation. What should they add? (more sugar / more salt / more fat / more fibre (fiber)) → more fibre (fiber)Prompt: Which nutrient keeps food moving through the gut?

Hook · 3 min

  • Ask everyone to find their pulse, then jump for 30 seconds and find it again.
  • Share the objective: Test foods for starch, sugar, protein and fat. Read the success criteria together.

I do: model it · 7 min

  • Work through the example out loud, saying why you do each step, not just what you do.
  • Example: A food sample gives this result: iodine turns blue-black. Which nutrient is present?
  • Step 1: Iodine solution turns from orange-brown to blue-black with starch.
  • Step 2: So the answer is: starch
  • Answer: starch
  • Pause after each step and ask a student to say what comes next.

We do: guided practice · 6 min

  • Do these together. Students try each step on whiteboards before you reveal it.
  • Use the hints as prompts rather than giving the answer.
  1. A food sample gives this result: Benedict's solution turns brick-red when heated. Which nutrient is present? (starch / sugar (reducing sugar) / protein / fat (lipid)) → sugar (reducing sugar)Prompt: Each test is used for just one nutrient.
  2. A food was tested. Iodine: stays orange-brown. Benedict's (heated): brick-red. Biuret: stays blue. Which nutrients does it contain? (protein / starch and protein / sugar and protein / sugar) → sugarPrompt: A colour change means the nutrient is present.

You do: independent practice · 7 min

  • Students work on the student sheet. Circulate and check the first two answers of every student early.
  • Students who finish: write a question of their own for a partner, with the answer.

The 6 questions are on the student sheet below, with answers in the key.

Exit ticket · 3 min

  • Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
  1. A student adds iodine to plain water as well as to the food samples. Why? (to save iodine / as a control to compare the colours against / to make the iodine stronger / to test the water for protein) → as a control to compare the colours againstPrompt: What would a negative result look like?
  2. A food sample gives this result: iodine turns blue-black. Which nutrient is present? (starch / sugar (reducing sugar) / protein / fat (lipid)) → starchPrompt: Each test is used for just one nutrient.

Watch out for

  • Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
  • Remembering facts without the reason: ask "why?" and "what is the evidence?"

Support and stretch

Support

  • Review first: Food groups, nutrients and what each one does.
  • Use concrete materials: stopwatches.
  • Give the first step of each question, or a partly worked example to finish.
  • Pair with a confident partner for the guided practice.

Stretch

  • Explain a common mistake in writing and how to fix it.
  • Write a word problem that uses today's skill, then solve a partner's.

Homework and more practice

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-7.

Free lesson plan from eurekami.com/lesson-plan-builder

eurekami

Test foods for starch, sugar, protein and fat

Name

Date

Score/ 6

  1. Question 1

    A food sample gives this result: ethanol then water gives a cloudy white layer. Which nutrient is present?

    • A. starch
    • B. sugar (reducing sugar)
    • C. protein
    • D. fat (lipid)

  2. Question 2

    A food was tested. Iodine: blue-black. Benedict's (heated): brick-red. Biuret: purple. Which nutrients does it contain?

    • A. sugar
    • B. starch and protein
    • C. starch and sugar and protein
    • D. protein

  3. Question 3

    Why should you wear eye protection when doing the Benedict's test?

    • A. The food might explode
    • B. Benedict's solution is radioactive
    • C. It involves heating in a hot water bath and the reagent is an irritant
    • D. Iodine glows in the dark

  4. Question 4

    A food was tested. Iodine: stays orange-brown. Benedict's (heated): brick-red. Biuret: stays blue. Which nutrients does it contain?

    • A. sugar and protein
    • B. starch
    • C. protein
    • D. sugar

  5. Question 5

    A student adds iodine to plain water as well as to the food samples. Why?

    • A. to save iodine
    • B. to make the iodine stronger
    • C. as a control to compare the colours against
    • D. to test the water for protein

  6. Question 6

    A food sample gives this result: biuret solution turns purple. Which nutrient is present?

    • A. starch
    • B. sugar (reducing sugar)
    • C. protein
    • D. fat (lipid)

Free from eurekami.com

for the adult only

Answer key: Test foods for starch, sugar, protein and fat

  1. 1. D. fat (lipid)

  2. 2. C. starch and sugar and protein

  3. 3. C. It involves heating in a hot water bath and the reagent is an irritant

  4. 4. D. sugar

  5. 5. C. as a control to compare the colours against

  6. 6. C. protein