Statistical analysis of the results revealed that the PLON students experienced
the lessons of the context-based unit Traffic as more reality- and activity-centred than students in the traditional course (Wierstra and Wubbels 1994 ) .
Furthermore, other evaluation studies of the PLON project confirmed this result and
showed that in most cases reality-centredness also promoted student appreciation of
physics lessons (Wierstra 1990 ) .