With my eldest DD she started school at 4 but turned 5 only a few weeks later. We have had to repeat her in Year 9 and she is now doing heaps better. My boys didn't start until they were turning 6 and they have had no troubles what so ever. My DD2 turns 5 next January and I will be asking her preschool teachers if she is ready. If they decide not then I will hold her back as well. I have no issues with school starting age but I do go on what my child is capable of handling.