How exciting that you know what you are interested in today! There are many organizations out there that offer fun and exciting camps related to engineering. Some schools even have special programs. Many offer scholarships or are offered for free and some are offered for girls only. My advice to you is to get involved in an engineering program as soon as possible. If you need help looking up and reviewing offerings just let me know and I would be glad to help you.
Also, engineers are creative and make stuff :). So start building things now (and keep in mind you don't need a camp to get started). Whether it is a small game you create online with an online tool, like courses done on code.org. Or if you decide to play around and build something cool with a raspberry pi like projects shown here: http://www.pcadvisor.co.uk/how-to/desktop-pc/10-great-raspberry-pi-projects-for-kids-3589952/
I got involved in engineering like activities when I was in high school. I loved art and loved using the computer to develop art pieces. But unfortunately I didn't have real exposure to engineering until college. However, today there are so many more opportunities for young ladies like yourself.
Again, if you have anymore questions feel free to let me know. And have fun on your engineering path!!