Activity 2 – Coloured Containers

Teacher: Look at these four containers: A, B, C, and D. What variables can you see immediately? What values do the colour and size variables have?

Maya: Red and blue

Teacher: So what are the two variables? Maya what do you think?

Maya: Oh I mean Size and Colour are the variables. Size has small and big. Red ones are big.

Rina: That is the relationship between size and colour

Sam: That means If the colour is red the size will be large. Also If the colour is blue the size will be small.

Teacher: That is an interesting way of putting it.

Sam: Well before we talked about predicting. Using if something then something else is a good way of predicting

The teacher passes the 4 containers around so the students can feel how heavy or light they feel. She hears all of their experiences and they reach a consensus that A feels light B feels heavy C feels light D feels heavy and writes this on the board. Then the teacher confirms by using the mass balance. At this point the teacher adds A has a low mass B has a high mass C has a low mass and D has a high mass. (It is not necessary to discuss the difference between weight and mass at this point).

Teacher: Does size always predict weight? What does it mean if a large container can be light and a small container can be heavy?
Is there a relationship between size and weight in this set?

Rina: No, you can’t predict weight from size.

Teacher: So does this give us an example of variables that are not related. Why might scientists need to understand cases where there is no relationship?

Samantha: To know what doesn’t cause something.

However the lack of mass to size relationship causes some considerable conflict. The connection with large and high mass is a very strongly held intuitive idea. Often the idea of No relationship causes a good deal of cognitive conflict. Piaget stressed that understanding a concept is often understanding what it is NOT.