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The Whole Bite Club
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The lesson plan, then the notes for every slide. Print on A4 and take the second sheet to the board.

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The Whole Bite Club · Prep to Year 2 · Lesson 3 · After the visit

What causes tooth decay?

Following the Whole Bite Club visit, students explore what causes tooth decay (dental caries). They will discover that decay is a kind of infection — germs in the mouth use the sugar in our food to make acid that can harm our teeth — and that the foods and drinks we choose affect how well our teeth are protected.

Learning intention

In this lesson, we will learn what causes tooth decay, and how our choices help protect our teeth.

Success criteria

I will know I am successful when I can:

  • Explain that tooth decay is caused by germs, sugar and time.
  • Explain that germs in our mouth use sugar to make acid that can harm our teeth.
  • Sort foods and drinks into everyday choices and sometimes choices.
  • Explain why water is the best drink for my teeth.
  • Suggest one choice I can make to protect my teeth.

Guiding questions

  • What is tooth decay (a cavity)?
  • What do you think causes a cavity?
  • Which foods and drinks help protect our teeth?

Vocabulary

tooth decay · cavity · germs · infection · acid · sugar · everyday foods · sometimes foods · water · plaque · protect

Australian Curriculum

AC9HPFP06, AC9HP2P06

Support

  • Provide pre-cut picture cards of foods and drinks for students to sort into “everyday” and “sometimes.”
  • Use a simple picture sequence (germs plus sugar make acid, acid makes a cavity) for students to order.

Challenge

  • Students look at everyday packaged foods and drinks and find where sugar is listed.
  • Students design a “tooth-friendly” lunchbox and explain their choices.

Resources

  • Foundation – Year 2 Supporting Resource Pack
  • Picture cards or empty (clean) food and drink packaging
  • Simple diagram showing how a cavity forms [OHH to insert linked resource]
  • Short video about tooth decay and sugar [OHH to insert linked resource]

Worksheets to print

  • What causes a cavity? · /downloads/what-causes-a-cavity-worksheet.pdf
  • Helps my teeth or not? (sorting worksheet) · /downloads/helps-my-teeth-or-not.pdf
  • Food cards to cut out · /downloads/food-cards.pdf
  • Sugar detective · /downloads/sugar-detective-worksheet.pdf
  • Lesson 3: What causes tooth decay? (PowerPoint) · /downloads/decks/f-2/03-what-causes-tooth-decay-slides.pptx
Oral Health Home · admin@oralhealthhome.com · www.oralhealthhome.com. Lesson text is reproduced from the Whole Bite Club teacher guide.

What causes tooth decay? · handout for the whiteboard

Teacher notes, slide by slide

The number beside each note is the slide it belongs to, counting from the first.

  1. 1.TitleWhat causes tooth decay?

    In this lesson, we will learn what causes tooth decay, and how our choices help protect our teeth. Recall the Whole Bite Club visit, when the Oral Health Home team checked everyone's teeth and talked about looking after the whole mouth.

  2. 2.QuestionWhat is tooth decay (a cavity)?

    Ask the guiding question: What is tooth decay? Explain simply that tooth decay is when a tooth gets a hole in it, called a cavity.

  3. 3.QuestionWhat do you think causes a cavity?

    Ask: What do you think causes a cavity? Record responses.

  4. 4.SlideGerms, sugar and time

    Explain that everyone's mouth has tiny germs — some of these germs cause tooth decay. Tell the simple story: the germs use the sugar in our food and drinks to make acid, and the acid can make holes (cavities) in our teeth. Decay happens when germs, sugar and time work on a tooth.

  5. 5.PictureHow a cavity forms

    Point at the weak spot on panel three before the words go up.

  6. 6.SlideHow a cavity forms

    Oral Health Home's own diagram, in four panels: plaque and sugar, acid attack, a weak spot, a hole. Read them in order, point at the weak spot on panel three, then cover the screen and ask the class to say them back. Support: use a simple picture sequence (germs plus sugar make acid, acid makes a cavity) for students to order.

  7. 7.SlideDecay is a kind of infection

    Explain that tooth decay is a kind of infection caused by germs — which is why keeping our teeth clean and keeping germs down helps protect them (this links to Lesson 4).

  8. 8.VideoTooth decay and sugar

    Short video about tooth decay and sugar [OHH to insert linked resource]. Play it before the sugar guessing game so children have the idea of hidden sugar.

  9. 9.GameSugar detective

    Children slide a spoon counter to guess the teaspoons of sugar in each drink, then watch the real number pour in. Challenge: students look at everyday packaged foods and drinks and find where sugar is listed.

  10. 10.SlideEveryday and sometimes

    Introduce everyday foods (good to eat most of the time) and sometimes foods (okay now and then, but not every day). As a class, sort a range of food and drink cards into everyday and sometimes. Discuss where sugary drinks and snacks belong, and why.

  11. 11.GameEveryday or sometimes?

    Children sort food and drink cards into the Everyday basket or the Sometimes basket. Support: provide pre-cut picture cards of foods and drinks for students to sort into “everyday” and “sometimes.”

  12. 12.QuestionWhich foods and drinks help protect our teeth?

    Guiding question. Steer the answers towards water and everyday foods, and towards eating sugary things less often rather than never.

  13. 13.SlideWater is the best drink

    Discuss why water is the best drink for our teeth and bodies. In many places, our tap water also helps to protect our teeth. Ask students to think about what they drink during the day and when water could be a good choice.

  14. 14.SlideHealth messages we can read

    Look together at health messages on food and drink packaging or posters. Discuss what the messages are telling us, and why (linking to health messages in our community).

  15. 15.WorksheetWhat causes a cavity?

    Worksheet: What causes a cavity? Students order the germs–sugar–acid–cavity sequence and/or sort everyday and sometimes foods, and complete the sentence: One choice I can make to protect my teeth is…

  16. 16.RecapProtecting our teeth

    Review the key message: decay is caused by germs, sugar and time; water and everyday foods help protect our teeth; and keeping our teeth clean keeps germs down. Students share one tooth-friendly choice they will try.

Oral Health Home · admin@oralhealthhome.com. Prototype handout.

Where this comes from

  1. The Whole Bite Club Teacher Guide · Oral Health Home. Held by Oral Health Home; not published online. The Foundation to Year 2 lessons themselves. Every lesson in this band is transcribed from the guide without paraphrase, so the guide is the source for the plan as well as for what it teaches.
  2. Tooth decay - young children · Better Health Channel · Opened 5 September 2026. That germs in the mouth feed on sugar and make acid, that the acid damages enamel, and that spit repairs the damage until the damage outruns the repair. https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/tooth-decay-young-children
  3. Policy Statement 2.2.2 - Diet and Nutrition · Australian Dental Association · Opened 5 September 2026. That drinks and foods high in sugar or acid are a sometimes choice for children, and that sugar and acid together are the harder pair on teeth. https://ada.org.au/policy-statement-2-2-2-diet-nutrition
  4. The majority of Queensland councils are washing their hands of fluoridation under the watch of both sides of politics · ABC News · Opened 5 September 2026. Why the lessons say tap water helps protect teeth in many places rather than everywhere: about 72 per cent of Queenslanders have a treated supply, and most councils have stopped treating. https://www.abc.net.au/news/2025-09-27/qld-fluoride-water-supply-tooth-decay-politics-washing-hands/105820504
  5. Australian Dietary Guidelines: Summary · National Health and Medical Research Council, Eat For Health · Opened 5 September 2026 · PDF. That the drinks and snacks this lesson calls sometimes choices are the discretionary ones, to be had only sometimes and in small amounts, and that whole fruit comes before juice, which is why juice is a sometimes drink rather than a bad one. The summary does not use the words everyday and sometimes for food; Health and Wellbeing Queensland, below, is the source for those. https://www.eatforhealth.gov.au/sites/default/files/files/the_guidelines/n55a_australian_dietary_guidelines_summary_130530.pdf
  6. Talking to kids about the foods we eat and why · Health and Wellbeing Queensland · Opened 5 September 2026. Everyday and sometimes as the words for food, and why the lessons use them: they describe what a food does without calling it good or bad, which is the whole point of the sorting activity. https://hw.qld.gov.au/blog/talking-to-kids-about-the-foods-we-eat-and-why/