+0

Are both okay: We haven’t formally started teaching the children yet.

And

we haven’t started to teach the children formally yet.


Whats the the difference?

+1
anon006What's the the difference?
anon006We haven’t started to teach the children formally yet.

You are teaching your children using informal methods. Education by using formal pedagogical methods will start in the future.

anon006We haven’t formally started teaching the children yet.

You haven't actually started teaching your children according to your definition of the word "teaching."