We're glad to hear you are interested in becoming a robotics engineer! You are definitely on the right track; anything STEM related (that's
Science,
Technology,
Engineering, and
Mathmatics) is always a plus. One thing you will notice early on is that all of the robotics fields have one major thing in common; the "M", or Math. Whether you decide to go with more of a hardware engineering path, software engineering path, or somewhere in between, having good math skills will be key.
From a broad perspective, I would suggest taking a look at any of the core classes that your school may offer (such as physics, computer programming, computer aided drafting, electronics, etc). This will not only help you establish a broad base to start from, but it may also help you narrow down what you would like to focus on. Don't be afraid to take classes that may not seem strictly robotics-oriented, either; a web programming (generally HTML) class can be a great alternative to a C/C++/Java class and is an awesome way to get started with programming. Same thing with classes such as chemistry, which can introduce you to core concepts that are used in electronics, and physics, which will teach you the basic principles that are used in mechanical engineering.
Don't be afraid to join after-school clubs, either. It's definitely worth looking into a robotics club (if your school has one) or an alternative, technology-based club.
And of course, never be afraid to ask questions! We are always happy to help with any questions you may have (except with homework; we will generally guide you with homework problems, but you will need to do the majority of the work on your own)

I will dig up some resources for you as well and post the links on here, I don't have them available right this moment but should have them soon.
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And this is crazy,
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