Feed
This site publishes an RSS feed of everything written in the Piazza. If you use a feed reader — and I hope you do — you can subscribe here:
The feed includes full content, not summaries. Each entry carries its maturity stage (stone, wall, arcade) as a category, so if your reader supports filtering, you can watch for pieces as they develop.
If you don’t have a feed reader, Miniflux, NetNewsWire, and Feedbin are all good. The protocol is RSS 2.0 with Atom extensions.