Teachers need to present material more recursively, revisiting concepts for those children who were not yet ready to understand the concepts when they were first presented. Teachers need to accept children where they are and help them move to the next stage of development. You do not scold that child for not knowing the correct grammar. You continue to model the correct way of speaking, praise the child for what he does well, and hold high expectations that, eventually, through your modeling and instruction, he will learn to say it correctly. Reading and writing need to be presented similarly.
Young children learn to read and write at different times, in different ways.
Many teachers and schools do acknowledge these tenets. They have modified and restructured programs and have reshaped their approaches using multiage classrooms rather than traditional grade levels. They use a variety of flexible and cooperative grouping strategies. Schools need to devote more time to staff development. Colleges need to continue to focus teacher preservice education on the developmental aspects of learning and how these translate into classroom practice.