i think 30040 can work as a lesson, it is metadata for collections of content.
Would need to see the difference between what a course offers vs a 30040 lesson. If you're linking them all together, a 30040 would be suitable. We have very nested content with 30040 & 30041: bible -> books -> chapters -> verse on Alexandria. So a course could be:
course -> week -> lesson -> section could work out. Quizzes would need a different kind though, because those are the sections.
https://njump.me/naddr1qvzqqqrcvgpzplfq3m5v3u5r0q9f255fdeyz8nyac6lagssx8zy4wugxjs8ajf7pqyf8wumn8ghj7mn0wd68yv339e3k7mf0qyw8wumn8ghj7un9d3shjtnhd94kjenjv4jkg6tp9eu8j730qyghwumn8ghj7mn0wd68ytnhd9hx2tcqpphxkcnfwqknqvg0800wp