Search for the roots of ratio: Some thoughts on the long term learning process (towards ... a theory)

According to the view of several experts which have been reported in part I, (Streefland, 1984) ratio requires a long term learning process. In the present part features and tools to outline and shape the longer term learning process for ratio are exhibited and elucidated by examples. Particularly instigating ratio-anticipating activities and creating visual models and schemes. The search for sources of the concept of ratio results in what might be called germs for a theory of teaching and learning ratio.