Below is a Progresso Cluster User Dashboard which uses 2 widgets (previously posted on this blog) but the establishment parameter in each widget points at a different school within the cluster. Hey presto! I can see a summary of a number of schools on a single page.
But what about viewing many schools data within a single widget you ask? Well I call those true cluster widgets. The establishment parameter in these type of widgets is a multi-choice field, so you can select just the schools you want (e.g. only the primaries within my trust, or just the secondaries as displayed in the dashboard below - Starters and Leavers).