As much as I hated schooling, I do want to say that there are parts of learning that are simply hard. There are parts that you can build enthusiasm for with project work and prioritizing for engagement. But there are many things that people should learn that will require drudgery to learn and won't excite all people.

Doing derivatives, learning the periodic table, basic language and alphabet skills, playing an instrument are foundational skills that will require deliberate practice to learn, something that isn't typically part of project based learning. At some point in education with most fields, you will have to move beyond concepts and do some rote memorization and repetition of principles in order to get to higher level concepts. You can't gamify your way out of education, despite our best attempts to do so.