March 8 is International Women’s Day, a holiday designed to empower all women and to celebrate activists dedicated to securing women’s rights around the world. In honor of this important day, we’re highlighting three girls who are using their girl-power to make a real difference.

Marley Dias

An avid reader, 13-year-old Marley Dias give new meaning to the age old saying “Be the change you want to see”! Two years ago, Marley began to notice that most of the books she was reading featured Caucasian leads – and often boys. So, she set a goal to gather 1,000 books featuring African American girls as their main characters, which she planned on donating to make sure that girls everywhere felt represented by the books they were reading.

A typical tween, Marley took her effort to social media with a hashtag #1000BlackGirlBooks. She has long since surpassed her goal of 1,000 books, gathering more than 9,000 books to date.

But that’s not all! Scholastic Press was so impressed by Marley’s problem-solving initiative, that they backed her own book, Marley Dias Gets It Done: And So Can You! In her book, Marley shares tips and tricks to help girls everywhere make their dreams come true. 

Gitanjali Rao

After reading about the ongoing issues residents of Flint, MI were having with contaminated water, 11-year-old Gitanjali Rao designed her own device to test the lead content in drinking water. She called her device the “Tethys” and believed that it would be more accurate than testing strips and less expensive than obtaining test results from a professional lab.

The scientific community agreed, awarding Gitanjali “America’s Top Young Scientist” honor and $25,000 to develop her concept. In true tween spirit, the Tethys uses Bluetooth to transmit the results of her test to a smartphone app, which shares the test results with users instantaneously. 

Sky Ballentyne

Britain’s Sky Ballentyne took it upon herself to up the safety anty for new cyclists with an invention designed to keep kids safe while they were learning to ride. At the age of 11, Sky designed the Crikey Bikey Harness to help parents hold on to their kids, rather than the bikes.

Something like a backpack with a long pole handle attached to the back, parents could hold on to the handle while running behind the bike, steadying their child, rather than the bike, when things got rocky. If the bike tipped or bucked, the parents had their kids in hand.