As a teacher I think this is a contradictory topic. It is true, that children are capable to learn and do learn huge amount of things even when they are in the womb. It can be very beneficial to help them orientate their attention towards linguistic and mathematical matters, so that they develop an interest towards these kinds of things.

But this is exactly what shouldn't be forced in my opinion, nor is the actual teaching of these subjects before school age, because there is a high risk of teaching certain things, problem solving or thinking in ways that make learning harder in the long run. There's a justifiable reason why certain things are taught in a certain order, so that ones thinking develops in a logical way.. So for example if someone teaches their children to read at home, there are many risks of going wrong there when it comes to future learning (You should lear the written and alphabets and maching phones/sounds, how to combine letters into syllables, words and then sentences etc) and all this should be learnt in logical order so that these skills support each other the best way. This applies at least in Finnish language which can be quite complicated…

p.s. Please excuse my English, it is not (as you can see) my native language, so it can be quite difficult to write about these kinds of complicated (yet so interesting imo) subjects in English.