Abstract
Students experience a range of difficulties in generating effective diagrams. Hence, it is important to explore these difficulties so they can be addressed during instruction on diagram generation. A cross-study comparison of the results oftwo network tasks revealed that students experience similar difficulties on feature-similar but non-isomorphic tasks. Students' difficulties on these tasks appeared to be due to a lack of sense-making. in mathematics rather than a difficulty with the problem structure or the generation of a particular type of diagram.