3 summer babies here - me, DH & DD.
DH - went to a fantastic primary who recognised him as very bright early on & supported him. He passed the 11+, went to grammar then Oxbridge & has a good job.
me - went to an ok primary, spent a year or in a mixed year class with the year below, failed the 11+ by 2 marks, went to a sink school, poor univiersity, have an ok job.
DD - very bright but was never in top groups in KS1 & got bored & disruptive. Passed entrance test for a very good prep for year 3 & has since been in top groups for everything doing very well.
None of us are very sporty or sociable though. DD really struggles with hockey as the young unco-ordinated one which is made worse by being left-handed. She is however, very good at gym. We are all also very musical.
I don't believe there are many teachers that are able to differentiate by ablity and age anymore. The national curriculum doesn't let them
.