And also do not be too quick to shoulder the blame for this squarely on your own shoulders. By the time your child is seven, she is quite canny, and knows how to listen to all sorts of crap that might get discussed at school. You know, there is always one kid, at least, who is more advanced for her age than the others, and these may be the ones who pick up on these messages regarding women and weight and aesthetics from their own families, from TV (a very powerful influence our kids absorb without knowing they are doing it) and bring them into school yard chat with the other girls in the gang.
So, while this does not help the fact that it seems already to have reached home, don't think that you are "to blame", don't accept guilt so readily, and please don't assume you are the only one whose child (fgirl, sadly) has picked up on this.
Why don't you try sounding out, very subtly beause you don't want to be seen to be seeking to lay blame on any other mother, the other mothers at school pick up time or at some social, and see if their girls have said anything similar. If the answer is yes, I would immediately approach both the teacher of these girls and the principal, let them know what messages are getting through to the girls, that you are concerned, that you know the negative consequences these ideas can have when they starrt so young, and ask them to discuss this in the classroom, bring it into the curriculum in some way. They are educators, they should know ways to do this, without specifically targeting some girls over others to receive the "educational message". If the other mums answered "yes" to your questions, then ask them to assist you in getting the school to help with this workshop.
The harm these thoughts can do to the next generation of girls needs to be stopped in its tracks today.
Thanks for listening!!!!
And good luck. You have all of my support.
Clare