The Dimensions-approach and the envisioned ongoing thematic learning processes require and realise a transdisciplinary understanding of phenomena.
OPEDUCA-based Learning is per definition all-encompassing from the perspective of school-subjects and disciplines, not because ESD makes them so but because they are from nature.
An interdisciplinary approach is required to address an issue comprised of (parts of) two or more disciplines, the joining issue.
Multidisciplinary concerns the disciplines an issue comprises, two or more ‘engulfed’ by the issue.
Transdisciplinary regards issues that don’t belong to the realm of one or an assembled group of disciplines and can only be addressed as joint effort.
In OPEDUCA all subjects and issues students learn on are connected, intertwined, part of a logical whole in which pathways of learning are discovered and researched by the students. Compare the neural structure of our brain. Typically students, great to be observed in puberty age, 'run from left to right, back and forth, up and down' in their thinking and acting - they 'jump around', often not focused on one thing, at least giving the impression to be occupied by everything at once and not concentrated. They are (like younger students also) however masters in associating - a quality, as teachers building OPEDUCA note with some regret, the average educator has lost along the way. For Inquiry Based Learning however the quality to link, re-link, associate, combine, connect is essential. And far away from subject driven instruction practice.