These are from a YouTube channel called
Harry Potter Theory which just started in March of 2019.
There are about 50 short videos so far. Most are three or four minutes long, though there were a couple a minute or two longer. While they just go over canon, you easily see they've done a fair bit of thinking and that they pull together tidbits from lots of different areas of the books to compare and contrast.
FYI - The titles don't always seem to match up with the heart of the subject matter in a particular video, and I didn't find much that we haven't already discussed here, but its fun to be reminded about things.
Here are some links to four of the earlier ones. Click on the ones at the top of the right-side column that these links take you to for the rest
: Top 5 Most Powerful WandsWho Created the Dementors and How?Who Taught ALBUS DUMBLEDORE? Why Professor Flitwick looked SO different