Spooky Spaghetti Worms in 7 Steps

This Halloween science experiment for kids dyes spaghetti purple with red cabbage water, then turns the worms pink with a squeeze of lemon juice.

 

Materials you’ll need

• red cabbage
• spaghetti
• water
• lemon
• baking soda
• knife and cutting board (ask a grown-up to handle this)
• pot (ask a grown-up to handle this)
• strainer
• tongs
• plates
• dirt

⚠️ Warning: Grown-ups only on the knife, the stove, and the boiling water. Turn pot handles toward the back of the stove and keep kids clear of the steam. Never strain or pour the boiling cabbage water with kids standing nearby. Let the spaghetti cool completely before kids touch it, and once the worms go in the dirt, they’re for play only, not for eating.

Step-by-step tutorial

Step 1: Have a grown-up chop a red cabbage into small pieces. Put the pieces in a pot and add enough water to cover them.

Step 2: With grown-up help, boil the cabbage until the water turns deep purple.

Step 3: Have a grown-up strain out the cabbage pieces and pour the purple water back into the pot. Bring it back to a boil and add the spaghetti.

Step 4: Stir the spaghetti and let it cook until it’s soft and purple all the way through. Have a grown-up lift it out with tongs, then let it cool.

Step 5: Spread dirt on a plate and pile your purple worms on top. Set a few worms aside on a clean plate for the bonus round.

Step 6: Squeeze lemon juice over the worms and watch them turn pink! Toss them around in the dirt to make them extra creepy.

Step 7: Bonus: Mix baking soda with water and pour it over the worms on the clean plate. Watch them turn green.

Learn more

Your worms change color because red cabbage is a natural pH indicator. Boiling pulls a purple pigment called anthocyanin out of the leaves, and the spaghetti soaks it up as it cooks. Anthocyanin molecules change shape depending on pH, a measure of how acidic or basic something is, and each shape shows a different color. Lemon juice is an acid, so it turns the worms pink. Baking soda is a base, so it turns them green.

If this project was a hit at home, Bubbling Cauldron takes acids and bases further by mixing citric acid and colored baking soda into a witchy brew that bubbles and boils when kids pump in water.