Last weekend, DC hosted the USA Science and Engineering Festival. This was the fifth biennial event, which started life in 2010 as an overgrown science fair spread across the National Mall and Pennsylvania Avenue. I have a few images on Flickr from that year, as well as from 2012 and 2016. Not sure why I missed 2014.
Unfortunately the Festival has turned into a commercial showcase dominated by government contractors, federal agencies, and the military. And, of course, everyone was into STEM. Sorry, arts people. I only saw one reference to STEAM.
Even with the excessive weaponization of science, there were some interesting exhibits and fun sights mixed in. Here are a few images from my time in the two huge halls, with the full gallery here.