“This is hard to understand as you can’t see the forces” exclaimed a student during a science course. Basic concepts in physics like force, energy, power are difficult to observe. Usually we often only make conclusions about their existence out of the resulting effects of their appearances. In addition, the use of similar words in other contexts, sometimes metaphorically, sometimes with other meaning, make the situation even worse. In science courses for pre-service primary school teacher students we have tried to design learning situations where students get personal experiences of the world behind the concepts described in words.

Thus, we designed situations when the students themselves were subjected to different forces or had the opportunity to observe the effects of forces. They wrote reflections on their experiences and we discussed these together in order to get used to how to describe and explain these type of experiences.

The learning outcome was assessed by analyses of written reflections of experiences from different attractions of an amusement park. One of the main outcomes of these reflections were the differences in the observations of the students. Often they had to do several rides to observe the forces they were subjected to. They also found differences in their personal ability to identify the forces. Some students were better in observing some of the forces than the others.

Thus, the participation in one activity with the aim of observing something does not necessarily lead to similar observations of other participants. Previous experiences seem to affect the observations so forces in some directions may be regarded as more powerful or easier to identify by some persons than others. This may be a general characteristic of observations in common situations. In that case this may be one explanation why, e.g., students have different focus in the classroom and learn other things than those intended by the teacher.