We weren’t formerly teaching math – but we were doing counting – and getting the 1-1 correlation between the number word “three” and three items around age 3… Both boys could do simple adding by age 4 (single digit addition). And both boys picked up simple subtraction before 5… which was ahead of their peers… We didn’t formally teach it – just did goofy games around the dinner table… (You have 5 green beans… You ate two – how many left.).
Both hubby and I are math nerds though, we enjoy math, puzzles, etc. – the boys are showing signs of having the same math ability and love of nerdly stuff.. They even started doing sudoku in kindergarten.
That said – different kids have different aptitudes… some of their classmates were reading at a much higher level, but not as strong at math… I imagine they’ll all even out at some point.
I know some of the signs they look for in “kindergarten readiness” is being able to count to 20, and having that one-to-one correlation between the number word and the # of items. (My sis the teacher made sure the boys were ready.)