3.3 Thinking in models

Example: Free fall

Course element	Work	Learning activity
Preparation Inventory of preknowledge and skills	Explanation or rehearsal of required scientific and mathematical concepts Operationalisation of preknowledge Use of apparatus and software	Class discussion Formative assessment Practical exercises

Before the modelling of free fall can begin, the concept of acceleration, and in particular the acceleration of gravity, must first be explained.¹

1. Students learn the definition of acceleration and can sketch the falling motion $$\begin{array}{l}a=-g\\ v=-g\cdot t\end{array}$$ in (y,t) and (v,t)-diagrams.
2. Students know the concept of force as a physical entity that describes the interaction between two physical objects and they know some examples, including gravitational force:
   $$F_{\text{z}}=m\cdot g$$
3. Students have some experience with a video analysis program, such as Coach.²

The teacher explicitly activates and assesses the required knowledge. Students train practical skills beforehand.