OK, first thing is not to go for really big needles use 4 or 4.5mm.
Start by casting on the project and knit a few rows and then let her start with garter (plain) stitch... you could use these rhymes
In through the front door
Once around the Back
Out through the Window
And off jumps Jack.
And if you want to get aggressive:
Stab 'em
Choke 'em
Drag 'em back
Throw 'em away!
And for purl:
Under the fence,
Catch the sheep,
Back we come,
Off we leap!
Use just 10 stitches to make a doll's scarf... use self striping wool, great for creating interest and saying, "just knit to the end of the red colour," and make mini pom poms for the ends... this will also help with handling the wool and manual dexterity. Do it in short bursts. Let her drop stitches and show her how you pick them up... you need to make mistakes in order to learn.
As she becomes more confident, then you can add on purl.... Then casting on and casting off... but most of all have fun!