I think the question I get asked the most is "where do you shop for your girls?". Mostly because this is a HARD age. They are too big for kid clothes but adult clothes don't seem right either. So I will share what works for us. I did a post back in the winter and this one is for summer. My girls are also picky. They ONLY want to wear t-shirts and shorts. I can talk them into a cute shorts romper sometimes. And a dress or romper for church. But I've given up on really cute clothes that I would like them to wear. ha!
Nike Running shorts are their #1 summer item to wear. And they are easy and basic. And the best price I have found is at Academy - they are $22.
To go with the shorts are t-shirts of any kind. We have school shirts, church shirts, etc but right now they love North face t-shirts. It's what they wear the most.
Life and Laundry tees has GREAT tees that are perfect for any age and they are soft. They are just our favorites! How cute is this for the 4th?
I got this romper to wear as a swimsuit cover up and I love it. It's soft and comfortable. It would work great for teens/pre-teens. It comes in a lot of colors and probably a small would fit younger girls.
This is super cute too for you or your girls!
I have had good luck at Target. I like Cat & Jack brand but my girls have almost outgrown it. But we have found cute things in the adult section that work.
This dress is so cute!
Target has all kinds of cute casual tees and shorts for girls too or you can get a dressier tee like this one for $12.
I'm loving the brand Habitual. They have SUCH cute stuff. This romper is 30% off. 
One of my best tricks has been signing up for Stitch Fix kids. They send a box to the girls and there is ALWAYS something that works for them. I got this jumpsuit for Harper recently. A lot of the things ya'll have asked me about - jumpsuits and outfits - have come from these boxes. Nothing is usually over $25 (you can set the prices) so it works great for us. You can sign up now and get $50 in free clothes if you use this link! (That's an incredible deal)
Other places I like:
H&M
Old Navy
Mango
Gap
And swimsuits I have mostly bought Target women's section.
It's work but shopping for a tween can be fun! Sort of. ha!
