The aim of the activity is to investigate whether ice melts faster in hot or cold water.
Younger children just love the idea of fishing and seeing the toy fish fall off the stick. If you have an older child this is a great experiment for learning how to work scientifically.
Water – warm and cold
Plastic fish (or other small objects/toys)
Ice cube tray
Place water into ice cube trays with fish ( or other small objects ) inside. Add a piece of string to each compartment. Make sure the string doesn’t end up in more than one section (otherwise they may stick together).
Once frozen, remove carefully and tie each ice cube to a stick.
Add warm water to one tub and cold water to another. Ask the child/siblings/parent to feel the water ( make sure it’s not too hot ) and predict which will melt the ice the fastest.
Place one fishing rod into each tub and start the timer.
Observe the changes to the ice every 30 seconds, how soon can you see the difference between the ice in the warm and ice in the cold water?
Watch for the fish falling out of the ice and record the time.
Were your predictions correct?
How does the ice change over time?
How can you tell which is melting the fastest?
What could you do to speed up the melting?
Can you try using hot, warm and cold water recording all the times taken for the ice to melt?
Are the results different if you carry out the activity outside?
Can you design a table to record your results?
Can you measure the temperature of the water? Does it drop as the ice melts? How big is the difference in temperature?