Not sure where you live... but I would imagine talking to other dance / yoga instructors of little kids in the surrounding area would give you some good ideas.... I know the parks / Rec dept near my parents house have special Yoga classes for kids and whole family yoga classes....
I've taught elementary children to dance for a year.... they were willing to work you definitely have to give them new goodies to work on and be an entertainer at times... and be willing to laugh with them.... Keep em busy and let's face it they will probably make it thru a 45 minute class tops then you may lose them..... I can also recomend keep most of it w/out trying to have them do the perfect poise... little minor adjustments here or there.... mostly tho kids want to have fun they are not interested in the perfection of a poise.... I can also recommend find as many fun descriptive words for each of the poises..... the more fun ways to describe poises the more it they will reach different kids...
Some kids may not mind you manipulating their bodies.... children such as your daughter may need to express their own boundaries..... What's important in my opinion is the children are getting the chance if they are interested.....
O.k..... that's my personal experience / advice... know of of no books... I like to check the library talk to reference librarians see what they can help you with if you want research material......

I teach yoga to preschool children. I can VOLUNTEER to give suggestions and work out a yoga curriculum for the children making it fun and exciting by making it age appropriate and also sequence the postures to suit children's physical abilities. I am currently starting to teach and devise a yoga curriculum integrating the theme or activities.
I am in east bay, if your place it around bay area, I could help you out.

Good luck!

I've seen really great success with kids dancing with music, doing short "partner" yoga sequences, and I just read about a class where the kids "row to yoga zoo"...