I think your problem resides on how to show the data. This link to data-to-viz has a diagram that might help you identify the best plot for your students and how each one of them sums up their contributions to the whole. 

[Data-to-Viz][1]

And this other web link might help you to find a use-case similar to yours.

[Betterfigures][2]


  [1]: https://www.data-to-viz.com/
  [2]: https://betterfigures.org/