It would be an understatement to say that girls feel pressured to look a certain way - or to conform to a certain standard of beauty. One Colorado mom is trying to change that.

On Thursday, which was International Day of the Girl, Dani Coplen released a new book called "Pretty." Its message aims to help young girl redefine how they measure their self-worth.

"I think for young girls right now our society puts incredible pressure on them to focus on their physical attribute and their appearance as the foundation of their self-esteem,” Coplen said.

Coplen said she got the idea when she realized she kept complimenting her daughters, only on their looks.

"They don't have to be just pretty,” she said. “They can be pretty brave, pretty kind, pretty smart. So I wrote the book as a reminder to myself to say those things to them on a regular basis."

When researching the book, she found that girls between the ages of 10 and 17 lose a lot of their self-confidence during those years. She wants this book reaches girls right before that age to help build their self-esteem.

"I hope after reading this, little girls can feel empowered to be whoever they really are and not feel pressured to look or be a certain way but embrace all of the pretty wonderful things that they are as an individual," she said. "This book is really for all the little girls out there, for all the pretty amazing things that they are and all the pretty amazing things that they will become."

You can learn more about this movement by joining The Pretty Conversation. Post a picture of the girl in your life accomplishing something amazing or a picture of yourself with a message to the younger you, using #strongsmartbold.

Some of the profits from the book with go to Girls, Inc of Metro Denver.