"Classroom studies document the fact that underserved English learners, poor students, and students of color routinely receive less instruction in higher order skills development than other students. Their curriculum is less challenging and more repetitive."

I've seen this before, and as a long time former high school teacher with at-risk kids I thought it was written by people who have never spent a second teaching a room full of academically struggling kids.

Let's say we are going to teach a youngster to build an Adirondack Chair. First they have to learn the tools, materials, and fasteners. If they can't master the safety element of carpentry, they simply can't move on to any other part of the proccess until they do. Then they have to learn how to use a tape measure, including the fractions. Again, if the student can't master measuring there is no point of them continuing until they do so. It will have to be repeated until they understand it. Now we are learning about scale and diagrams. If they can't move a process from a piece of paper to a piece of wood, it will have to be gone over until they can. Finally, after the student has mastered those skills, we are ready to pick up an actual tool besides a tape measure, but dang it's already the end of the quarter.

If a student comes into class knowing the tools, how to work safely, how to measure, and how to work with a diagram, they can get to work immediately on building the chair, and after that we can move on to building a sailboat. The kids who are struggling with the basics will be gluing together a pre-cut birdhouse, after we review those fractions again.