I look after my nephew a lot because his parents both work long hours (NHS.) Today he had a home visit from his teacher before he starts school next week. She bought some things with her as 'ice breakers' and, in her words, was 'absolutely amazed' by DN. She bought some five piece peg puzzles that my two year old has been able to do for months. DN showed her the 100 piece puzzle he'd completed that morning and she was gobsmacked. She asked some leading questions to see if he knew his colours and again was shocked that he did. Again, my DD can pick out colours and colour sort and she's two - DN has known his colours since around 18 months.
DN also demonstrated that he could read numbers 1-10 (he can read 1-20 but she didn't have the resources to stretch that far), read CVC words and use words like more, less, bigger, smaller, the same to compare objects and groups. She asked if he could recognise his name and was really shocked that he could read and write it.
I think reading the CVC words is a little ahead but don't most children know their colours and numbers by reception age? The teachers expectations seemed extremely low.