Hello Anne,
There are a few options you could try. Brent suggested regression analysis, which would estimate how much (if at all) certain school districts impact value (on average). From the CAMA perspective, lots of this information is hiding inside of our location adjustments. Make sure someone with spatial regression analysis is included in this process, otherwise you can come up with some pretty funky and misleading results (especially with all of the other factors correlated with location).
For the purposes you describe, you may just be fine with a map. I would recommend using the analysis feature in ArcGIS Online or ArcGIS Pro. Assuming you have a layer with the district boundaries, you can upload this with a spreadsheet of validated, arm's-length sales, merge the two, and then fill in the polygons with different colors that can convey information about the markets (e.g. median price per square foot). It's important to note with your maps that readers do not draw false conclusions and that there could be other locational influences or physical characteristics impacting values. If you end up going down a route where you are calculating school district adjustments for CAMA purposes, you definitely want to have someone with specific regression experience do this. Hope this helps! 🙂
