Best way to run dozens of queries?

[gnomeking_jasper]

I'm trying to produce a 'summary' report for a lot of different queries on one postgres database.  For example, one summary is 'Number and percentage of students achieving each grade' and another summary is 'Top 20 classes' (including class name, number of students, and class teacher).

So far I'm doing this using subdatasets and fixed jr:table elements in different detail bands - but that forces me to fix the size of the tables - so if new grades are added then my static formatting needs to be re-worked!

Is there a better way to present the output from many individual queries?

[gnomeking_jasper]

I realised the way to do this was to have many subreports with each sub-report in its own band so the band will expand to show all data from the subreport.