No matter whether you construct a short, a long, a free-standing, a wall-mounted, a colorful or a monochrome structure: There are no limits to your ideas. The only requirement is that the marble run must be largely made of paper and/or cardboard.
Why "marble runs"?
Marble runs can be built in a simple form even by kindergarten-children, but it's also possible to create more spectacular buildings for example in technical school classes, by companies, or by families. While building the tracks, the properties of paper and cardboard could be researched (e.g. the stability of the materials and/or the absorbency while gluing or painting the track-parts).
(e.g. for school classes, kindergarten groups, student groups etc.)
(e.g. for individuals, families etc.)