I also think assignments and projects work best, but only for the percentage of students that are self-motivated, curious, interested, etc. Unfortunately a lot

I also think assignments and projects work best, but only for the percentage of students that are self-motivated, curious, interested, etc. Unfortunately a lot aren't, they feel like they have to be there or these courses are the only path for them to get a good job. And unfortunately they end up in the workforce, too. You'll often see teams with one good developer and a lot of hangers-on.