Real Life doesn't come at us in 1 or 1.5 hour, subject-based increments. It comes to us all at once where we have to be ready to switch from one skill to the next with flow.
And rarely are we ever faced with solving a set of “ever-increasingly-difficult-section-of-math-problems-that-are-similar-but-not-quite."
If we're to be getting kids ready for Real Life then we need to be giving them Real Life Practice right now.
What is authentic in your schools right now?