Hi OP -
In that case, she is plenty old enough to be able to use Tutor Books (of which there are many different series) and many come with CDs, either for you to play along with, or to hear how it should be played.
She wants to play Pop - but there are so many different kinds of Pop these days, that she probably needs to pin it down more precisely. And 'modern' pop relies so much on weird effects, multi tracking etc, that it is very difficult to replicate it on an ordinary keyboard.
So, I'm afraid that many tutor books will feature 'old' Pop: Beatles, Tom Jones, Abba, right back to 'quality' songs by Frank Sinatra, the standard stage shows and musicals etc.
Has she done ANY music before (recorder, school percussion etc) so that she does know the basics? Or is she starting right from scratch?
One of the standard Keyboard tutors is by Kenneth Baker, and covers tuition books and 'song books' for when she can play a bit. Many book shops stock Kenneth Baker books, and he also does a series for Piano, and Organ (so don't get them confused.)
www.themusicpeople.co.uk/acatalog/The_Music_People_The_Complete_Keyboard_Player_7.html
[I am in the process of doing more advice on music for other people, in a week or so, so I will look back and send you that if it seems relevant.]