I created several using state and national Dept. of Education data. Very simple to do when using downloaded Excel workbooks. However, tapping into a data warehouse is quite different.
What SIS do you use? Did you have to do a lot of "clean up" on the excel sheet to get the data to work well with Tableau? We are very interested in posting DE data on the website.
We are stuck with a Lotus Notes based system called Harmony. It is a document management system, not a relational database system, so its less than ideal and we have to pull everything into a Data Warehouse to try and create clean class rosters, etc.
The data posted on our DOE website is pretty clean and fairly easy to use inside Tableau, but its all aggregate data. In terms of our own charter schools, we have to clean up the data in a big way before using Tableau.