How do you do it?

I've looked at youtube clips about blending words etc, sounding it out etc, but DD5 isn't grasping all sounds (eg if I ask her for the first sound in bat, she wouldn't sound it out and say 'b' (beh). But if I get her to do the same with mat, she'd reply 'mm'.

I found some lowercase alphabet cards and held them up making a big game out of 'what other things start with_____' and she was pretty good at doing it with all letters.

Am I expecting too much too soon? Its just that the teacher has told me that she knows all her sounds, but I'm not sure how she made that assessment - so much so that DD5 skipped ahead to learn spelling with a few of the other kids, whilst the majority of the year level stayed on learning the sounds. Now DD has been moved back to the sounds group - I'm not sure why we're going backwards?!?!