Are there any websites like Khan Academy that track student progress but are adaptable?

I'm not really sure how to word this. I've been using various online resources like Khan, Quizziz, Quizlet, etc for my middle school students and have seen great success. My school is finally to the point where my students should have daily access to computers and Id like to find a way to take it to another level.

Is there an online program where I could upload my own videos/tests/etc like Khan and give students game-like rewards to track progress over time?

If you can't think of anything or if that doesn't make sense what are some great online game-like resources for teaching language arts/social studies content. Thanks for the help!