Ask HN: Ideas for “Knowledge Snacks”

Hello, dear friends! I am trying to breathe life into my reddit community /r/gifexplainer which is dedicated to educational slide-based GIFs, that are like knowledge cards. The idea is to explore the possibilities of microlearning and create a community that creates and shares this type of educational content. I am planning to run a marathon of creating first 99 GIFs on my own. So I request your assistance in identifying 99 ideas from all areas of knowledge that have value for a common curious person and are easy to express in up to 5 slides. Thank you in advance!