Stretching Graph for Two Criteria on y-axis

[rylock]

I'm trying to make a graph to see the differences in student testing by age and their school rating. I could very easily make a scatterplot with student test scores by age and another for student test scores by school rating. But how can I get them on the same graph in a way that will tell me something?

I know how to use primary and secondary axes -- but those seem to show me how I would use those two graphs separately, just on the same graph. Which is definitely better, but not what I'm looking for. Since the idea is that there's only a correlation between age and rating, I think I'm thinking about graphing it the wrong way.

My hope was that the x-axis would be the 1-10 ratings, while the test scores would be one y-axis and the age would be the other -- but the score plots and the age plots wouldn't be so distinct.

Any suggestions? It might be less of a graphing question and more of a formulaic one (which is why I'll post it in general) -- but I thought that there was a way to manipulate this data and show the results by both criteria at once, rather than just showing both criteria separately on one graph.

Attached is a subset of some data and the graph I made that's not very helpful:
ScoringSample.xlsx

Thanks, any help is appreciated!

[Kaper]

If you want to "show" the influence of two criteria (rating & age) on a third one (score) you could give a try to bubble plot. The diameter of bubble is representation of the third variable in 2D space.

Otherwise, you shall probably go for proper 3D graph which is not so easy to obtain from scattered data in excel. (it is easy if you have a complete matrix of x and y and one Z value for each x,y pair).

But then there are some simple freeware tools see for instance gnuplot (as well as commercial packages) to do so.