I am a non musical parent, dd (7 and in year 3) has been having lessons for a year and a half and passed grade 1 in March.
I sit in her lessons and listen to what her teacher is asking her to practice and I have done so from the beginning. The teacher explained to me what kind of help would be required at home and what I shouldn't do (for example never write the note names on the score to "help" as this is not helping).
Her lessons involve the following: teacher listening on previously assigned pieces and correcting mistakes. This could be rythm, fingering, tehnique.
She then moves on to the next piece or the next level, left hand if she only did right hand previously on current piece, hands together if she only did hands separately previously, polishing the piece in terms of soft, loud, crescendo, or new piece if current ones is up to a certain standard of achievement. Sometimes she will play it for her to explain what is left to polish it.
When she assigns a new piece she will go through it with dd by sight reading.
At home dd is practising every day as it is part of a routine and dd enjoys it. What I do is sit on a chair and remind her what the teacher asked her to do (count out loud, put hands together, play softly, practice a certain difficult bar a number of times etc).
What I noticed is that if I take a real interest in her playing she will progress faster than just expecting her to do it on her own.
I am trying to keep up with what she is learning (not by playing myself) and I am quite good at hearing a wrong note and helping her to figure out herself which is the right note by using the tools the teacher gave her.