Science lesson plan · 7th grade (Year 8 in England) · 45 minutes
Trace a meal through the digestive system
Human body and health
CCSS NGSS.MS-LS1-3England: KS3 Biology: Nutrition and digestionEngland: GCSE Combined Science: Organisation
Objective and success criteria
Students will: Trace a meal through the digestive system.
- 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: The digestive system; Human organ systems and how they work together
Leads to: Digestive enzymes and the molecules they make
Materials: Stopwatches, Body diagrams, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (The digestive system; Human organ systems and how they work together). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Which organ system is this: lungs, trachea and bronchi? (nervous system / respiratory system / skeletal and muscular systems / circulatory system) → respiratory systemPrompt: Think about the main job: transport, gas exchange, digestion, control, movement or removing waste.
- What does the stomach do? (absorbs most of the water / chews food / filters the blood / churns food with acid and enzymes) → churns food with acid and enzymesPrompt: It has strong muscular walls.
- Which organ system is this: filters urea and extra water out of the blood? (nervous system / digestive system / respiratory system / excretory (urinary) system) → excretory (urinary) systemPrompt: Think about the main job: transport, gas exchange, digestion, control, movement or removing waste.
Hook · 5 min
- Ask everyone to find their pulse, then jump for 30 seconds and find it again.
- Share the objective: Trace a meal through the digestive system. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: What pushes food along the oesophagus (esophagus), even if you are upside down?
- Step 1: Peristalsis is muscle squeezing that moves food along the gut.
- Step 2: So the answer is: waves of muscle contraction (peristalsis)
- Answer: waves of muscle contraction (peristalsis)
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Where is most water absorbed back into the body? (liver / large intestine / stomach / mouth) → large intestinePrompt: It is the part just before the waste leaves.
- Food has just left the small intestine. Where does it go next? (anus / large intestine / mouth / stomach) → large intestinePrompt: Digestion and absorption happen before water is removed.
You do: independent practice · 10 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 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- Food has just left the stomach. Where does it go next? (mouth / anus / large intestine / small intestine) → small intestinePrompt: Digestion and absorption happen before water is removed.
- What pushes food along the oesophagus (esophagus), even if you are upside down? (gravity only / air pressure / the heart / waves of muscle contraction (peristalsis)) → waves of muscle contraction (peristalsis)Prompt: The walls of the tube squeeze.
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: The digestive system.
- 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: Digestive enzymes and the molecules they make.
- 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