Disappearing Water

An experiment to demonstrate evaporation


  • Two transparent glasses – preferably narrow cylindrical ones.
  • A marker.


  1. Fill both glasses with water almost to the top.Glass of water two weeks disappearing water
  2. Keep one glass on a window sill which gets sunshine
  3. Keep the other in a dark corner of the room, in a place where it will not hamper children’s movements.
  4. Mark the water level in both glasses with the marker.
  5. Every three days mark the water levels again.
  6. After two weeks, compare the water level in both glasses.

Note: Don’t forget to tell the cleaning staff not to touch this experiment.

Teacher’s notes:
Discuss evaporation of water and factors that aid evaporation. Ask children to state examples of evaporation that they see in daily life. If you are doing this exercise with younger children, ask them what they think has happened to the water.
If you would like to take the activity forward and demonstrate the water cycle, build a terrarium with the class.