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MCSA Lockdown Tip 43

MCSA Lockdown Tip 43

Lockdown Day 43 – Sinking and Floating

Knowledge and Understanding of the World.

Science is an integral aspect of how we come to know and understand our world.  The scientific process requires us to be methodical and ordered. These are good skills to develop for all future work in any of the sciences. Also important is opening the child’s eyes to possibility, allowing their imaginations to anticipate what is not yet there.

Coming up with a hypothesis, making a prediction, testing (creating a reaction), observing results and drawing a conclusion is all part of the scientific process. Try and emphasise these in our activity for today:



  • A plastic placemat/ clear work area
  • A large, fairly deep bowl
  • A large jug (to be able to fill the bowl at least halfway)
  • A plain coloured dishtowel
  • A cloth for any spills
  • A collection of smallish items from around the house. You may need to test prior to the lesson, because sometimes what we think will float ends up sinking and vice versa. Some ideas for items: key, cork, plastic lid, sponge, coin, ping pong/golf ball, pencil, marble, pebble, feather, Lego brick, teaspoon etc.


1. Ask the child to bring the placemat to the table.

2. Place the bowl on the mat and the container with the objects to the left-hand side of the placemat.

3. Open the dishtowel out and lay it to the right of the placemat.

4. Ask the child to fetch water in the jug and to fill the bowl at least halfway with water.

5. Take the objects out of the container one at a time, discuss the name, and what it is briefly, placing each object in a horizontal row above the bowl on the placemat.

6. Explain to the child that today we are going to be experimenting with objects that sink and objects that float. (Our HYPOTHESIS is that objects will do one of two things in the water. They will sink or they will float.) Invite the child to choose an object to start the experiment.

7. Once the child has chosen the first object, ask her/him to PREDICT whether s/he thinks it will sink or float.

8. Once the prediction has been made, invite the child to TEST the prediction by gently placing the object on the surface of the water.

9. OBSERVE what happens and encourage the child to describe what s/he sees.

10. DRAW A CONCLUSION from the observation analysis. For example, ‘Yes, you thought the string would float on the water and it did float!’

NOTE: Be mindful of drawing conclusions that are not accurate. It is not true for example that heavy things sink, and light things float. Huge, heavy container ships float!

11. Ask the child to place the object on the left-hand side of the dishtowel. Explain that you will be making two groups of objects after testing each one. The objects that float will be placed here (point to the left-hand side of the dishtowel) and the objects that sink will be placed here (point to the right-hand side of the dishtowel).

12. Invite the child to continue testing all objects, remember to make a prediction about each one before testing it. This is important for stimulating imagination and developing language!

13. Once all of the objects have been tested and placed on their appropriate sides of the dishtowel, discuss the findings again.

14. With older children, you can certainly explain that the objects that sank are made up of molecules that are very densely packed together, while the objects that floated, are made up of loosely packed molecules.

Do not be afraid to tell your child that you do not know the answer to a question they may raise! Google together and express your joy in learning alongside your child.

15. Conclude the activity by inviting the child to dry up the objects and put them back into their container. These can be kept for further experimentation when they are in the bath later in the day!

16. The water from the bowl may be used to water a pot plant. Help the child if necessary.

17. Dry up the bowl, jug and placemat and pack these away.

18. Hang the dishtowel on the line or put it in the washing basket if necessary.


Montessori said, “We need imagination in science. It is not all mathematics, nor all logic, but it is somewhat beauty and poetry.” We hope that you will discover this truth with your children