My DS9 was skipped into 4th at the beginning of this year. Everything went well except he had ups and downs with writing essays which was a big concern to the teachers because they test 4th graders writing. They grade the high stakes test on a rubric 0-6 point scale so all school year they do the same. Their writing is graded throughout the year by two different people, sometimes by teachers your class doesn't have, sometimes by your own teachers. He started the year getting scores of 2 and having problems just getting started on some essays. I felt like his struggle with writing was good for him. Just enough that he really had to work and learn but not so hard he couldn't do it.
Just last week they wrote another essay (the official writing test was in February) and he got a 5 on it. He was so proud of his five and how much easier it is to write these essays than at the beginning of the year.