Materials:
Tray (to catch the mess)
1 x empty soda bottle
1 x tsp yeast
2 x tbs warm water
a plastic funnel (to stop spillage)
1/2 cup hydrogen peroxide
4-5 drops of food colouring
a squirt of dishwashing liquid 
 
Place the empty bottle in the centre of the sheets of newspaper.
In a small jug mix together the yeast and warm water. Agitate it until bubbles form (you need to activate the yeast).
Use a funnel to pour 1/2 cup of hydrogen peroxide into the soda bottle. Add some food colouring and a squirt of dishwashing liquid.
Now add the yeast mixture to the bottle.
 
Watch the monster toothpaste rise up and ooze out of the bottle.
 

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