I know it's late, but I gotta say it: Uruka's teaching stream was unironically pretty good. I'm sure technically it may not meet professional standards, but so do a lot of working teachers's curriculums and hers was much better. It was well formatted and it's clear she understood the material. Some bits could have used some polish, but being her first time it's impressive still. I always love it when vtubers teach us about stuff or we learn stuff together, even if there not the best at it. Uruka was a solid 101 music teacher, though. Urufugang was a solid class too. There was a lot of meming, of course, but in the end they did take the class earnestly.
I didn't have any real expectations, but it was a 9/10 stream. May not be for every vtuber viewer, but it's good if you have any interest in learning a little more about music.