How to make a model volcano erupt
You will need:
Casting plaster , sand, water , paint and brush, plastic sheet or newspaper, a paper plate or a tray, containers for sand and water, red food colouring, baking soda, white vinegar, a funnel or a spoon.
1. Cover a table with newspaper or plastic.
2. Put some sand in a container and add a little bit of water.
3. Use the sand to make a cone shape on the newspaper.
4. Put some water in another container and sprinkle some plaster into it.
5. Mix the plaster into the water until it is as runny as a honey. You may need to add more plaster to make the mixture thick enough.
6. Pour some plaster over the sand cone and smooth it with a wet paint brush.
7. Make a hole in the top of the cone about as big as a ten cent coin.
8. Let the plaster dry for one day.
9. Remove the sand from inside the plaster volcano.
10. Make more plaster. (See Steps Five and Six)
11. Put the plaster volcano on a paper plate and pour some more plaster into the plate so that the edges of the volcano are all covered.
12. Let this plaster dry for one day.
13. Make more plaster. (See Steps Five and Six)
14. Pour plaster inside the volcano. Stop at about 3 centimetres from the top.
15. Let the plaster dry again for one day.
16. Paint the volcano.
17. Let it dry.
18. Put newspaper on the floor and on the table.
19. Put the model volcano on the table.
20. Use a spoon or a funnel to put the baking soda into the hole in the top of the volcano.
21. Put a little bit of white vinegar into a container and pour in some red food colouring.
22. Carefully pour this mixture into the top of the volcano and move back.
23. Watch the volcano erupt