Anyone who has studied educational psychology learns that not all children follow the same educational, psychological or emotional timetable. What I would like to suggest is increased grouping by skill level. It appeared to have resulted in reduced self-esteem, and so it was abandoned. I would submit that ignorance is far more damaging to self-esteem. If grouping is done in a positive manner, it carries with it many advantages.
Students can work at the appropriate skill level in all subject areas.
Students who bog down in one or more subjects can take the needed time to accomplish the tasks. Students do not move on until reaching a specified level of achievement. This eliminates the need for social promotion. It also has, built into the system, the ability to allow students who experience the emotional difficulties associated with being a child to take the time they need to do it right. Summer school could still be used to give students more time to complete their tasks and stay on the suggested schedule.