reading reading reading
I recommend to start with this
Natural Parenting ― Back to Basics in Infant Care
http://www.epjournal.net/filestore/ep05102183.pdf than
on tummy since the first day
you can do infant stimulation cards since first weeks (search google for this)
math, reading you can start with 3 months (I started math at 4, words at 7)
but be relaxed about it
I think, it is very important to give the possibility to develop fine motor skills. first months are important. I mean - toys with various texture, with rough surface etc., with various details.
If you will do math, I recommend to start with physical flash cards (you can print up to 40 dots on A4) and than switch to screen. So you will learn the system and the attitude.