Science lesson plan · 7th grade (Year 8 in England) · 30 minutes
Breathing, gas exchange and respiration
Human body and health
CCSS NGSS.MS-LS1-7CCSS NGSS.HS-LS1-7England: KS3 Biology: Gas exchange systemsEngland: KS3 Biology: Cellular respirationEngland: KS4 Combined Science: Cell biology
Objective and success criteria
Students will: Breathing, gas exchange and respiration.
- 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: Heart, blood and circulation
Leads to: Respiration without oxygen: muscles and yeast
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 (Heart, blood and circulation). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Ethan counts 24 pulse beats in 30 seconds. What is the pulse rate in beats per minute? → 48Prompt: How many lots of 30 seconds are there in one minute?
- What do arteries do? (carry blood back to the heart / make urine / carry blood away from the heart / digest food) → carry blood away from the heartPrompt: "A" for arteries, "A" for away.
- Blood and circulation: which statement is NOT true? (Veins carry blood back to the heart. / White blood cells help fight infection. / Blood is always red; it is bright red with oxygen and darker red without. / Blood in veins is blue.) → Blood in veins is blue.Prompt: One of these is a famous myth.
Hook · 3 min
- Ask everyone to find their pulse, then jump for 30 seconds and find it again.
- Share the objective: Breathing, gas exchange and respiration. 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: Where does gas exchange happen in the lungs?
- Step 1: Oxygen diffuses from the alveoli into the blood, and carbon dioxide diffuses out.
- Step 2: So the answer is: in the alveoli (air sacs)
- Answer: in the alveoli (air sacs)
- 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.
- What is the difference between breathing and respiration? (They are exactly the same. / Respiration only happens in the lungs. / Breathing moves air in and out; respiration is a reaction in cells that releases energy. / Breathing happens in every cell.) → Breathing moves air in and out; respiration is a reaction in cells that releases energy.Prompt: Where does respiration happen?
- Respiration: which statement is NOT true? (Mitochondria are where aerobic respiration happens. / Respiration produces energy from nothing. / Plants respire as well as photosynthesise. / Respiration happens in every living cell.) → Respiration produces energy from nothing.Prompt: Respiration and breathing are different things.
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 5 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.
- During hard exercise, muscles may respire without enough oxygen. What do they make? (starch / lactic acid / alcohol and carbon dioxide / oxygen) → lactic acidPrompt: This is anaerobic respiration in animals.
- Respiration: which statement is NOT true? (Respiration happens in every living cell. / Plants respire as well as photosynthesise. / Aerobic respiration releases more energy than anaerobic respiration. / Respiration produces energy from nothing.) → Respiration produces energy from nothing.Prompt: Respiration and breathing are different things.
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: Heart, blood and circulation.
- 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
- Move on to: Respiration without oxygen: muscles and yeast.
- 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