This was a tough read indeed. Dewey writes nearly entirely in abstraction. He rarely put concepts in terms simple to understand.
His great contribution, however, is he shows the importance of thinking. Foundational to all instructional work is thinking. Each lesson and unit requires thought. While lessons are in progress thought is essential. Upon the lesson’s completion reflective thought must occur.
Improved thinking requires training regardless of our thinking ability now. We improve thinking thru training. Train your thinking.