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🎃 This is one of our Halloween crafts, back in the spotlight from Friday, 1 October 2027 — but you can make it any time you like.

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Bubbling Cauldron Potion

Ages 4–10⏱ 20 minMess: HIGHGrown-up help: MediumKitchen Science
Professor O proudly stands beside the completed craft, gesturing excitedly with open hands toward the bubbling creation.

Professor O will help you learn: Mixing bicarbonate of soda with vinegar makes a gas called carbon dioxide, and a squirt of washing-up liquid traps it in bubbles so the potion foams up and over the cauldron like a witch's brew.

⚠️ Do this on a tray or outside. Vinegar stings if it gets in eyes, so keep faces back when pouring and wash hands afterwards. The potion is not for drinking. Food colouring can stain clothes and surfaces.

Play through the project step by step, with narration read aloud.

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Steps

Tap any step to play from there — the narration plays inside the player.

Make it your own: Try warm vinegar against cold vinegar and time which potion bubbles over first, or add a few drops of a second colour to make a two-tone brew.

📖 Featured in: October half-term activities to do at home · Easy Halloween crafts for kids

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