Pupils on Wednesday afternoon worked in mixed-age groups on a STEM (Science Technology Engineering and Maths) project to build bridges. We started experimenting with sheets of paper aiming to increase the strength of a span needed to carry weight across a 20cm gap. Limited to four sheets of A4 paper and 15 cm of masking tape, it was an interesting challenge. Cylinders and triangles seem to be the key to building a strong structure. We moved on to creating box girder bridges—again from paper and split pins.