I assume you've tried talking with your teachers about this, but if not, that would be my first recommendation. Be specific -- don't just say "I'm bored." Tell your teacher when exactly you were feeling this way. One word of caution, though: Telling teachers that you are bored in their classes can have an unexpected effect -- they may feel very insulted. A better way of saying this is: "I'd like to challenge myself more." See if you can make some suggestions about what would make the material more interesting to you. For example, if the class is studying Spanish verbs and you like to write, maybe you can write a play using those words. Or, if you like to cook, maybe you can do a cooking demonstration using those words. Or create a Spanish game for younger students. Another suggestion: Ask yourself how you would teach this material -- perhaps your teachers would welcome your recommendations!
If talking to the teacher yourself doesn't work, perhaps the teacher in your gifted program would intervene. She might be able to convince the teacher to allow you to learn about things in ways that she has found effective with you. Your boredom may be a matter of a mismatch between the teachers' teaching style and your learning style -- and that is something that teachers can talk about in a professional way.
Perhaps you would like to learn more about your own learning style -- and for that, I highly recommend a book by Dr. Kathleen Butler called Learning Styles: Personal Exploration and Practical Applications. This book is appropriate for people your age as well as for parents and educators. It's interesting and fun to learn about the ways in which you learn best, and that's information that will help you in many aspects of your life.
If all else fails, you might re-think the problem of boredom as a message that you're giving yourself that you need to do things differently. You have a choice. You can be bummed out by boredom or you can think of it as a challenge, something to conquer before it conquers you. So what are some little ways in which you might combat boredom at school? Here are some possible strategies:
* Alternate the school supplies you use. Use different colored notebook paper every day. Write with a different pen. Plan a monthly trip to buy new school supplies instead of buying the whole year's worth all at once. It may sound simplistic, but for some people, the novelty of different pens, paper, and the like really helps!
* Use "idea traps" -- like Post-Its or small notepads -- to record and collect the good ideas you have when you're supposed to be thinking of something else. Challenge yourself to keep up with what's going on in class while thinking your own thoughts. This is called "multi-tasking" -- and for some people, it's a preferred way of learning!
* Ask fun questions to yourself about whatever topic is being discussed, like: How could a clown use this information? How could my favorite movie star use this information? How could I use this information in spring, summer, winter, or fall? At midnight versus 8 a.m.? How might I use it ten years from now? How would I explain this to my dog? See how many different questions you can come up with in five minutes.
* Ask your teacher to let you sit in a different chair when you get bored. Tell him or her that the change in environment will help you stay alert.
* Play the game of opposites. If you're learning about multiplication, how is it similar to, and different from, its opposite, division? How is a comedy like and unlike a drama? How are girls like and unlike boys?
* Suspend rules of logic. Wonder about how a noun feels about being a noun, or whether a tree would rather be a bird, or whether the number three would rather be the number five.
Some of these may sound crazy but the whole point is to keep your imagination going and to keep you connected to the material that is being taught! Go to it!