i want to learn japanese but i' m too young for high school and my teachers french. can anyone help me?

Some Options:

i) Going to classes that are private taught such as at community colleges, schools, private institutes and tutors.
ii) Audio Books
iii) Workbooks and Phrasebooks
iv) Knowing a Native Japanese speaker would be helpful, or going to language meet-ups (if there are any) in your area to exchange languages.
v) Online & computer resources such as Pen Friends, online language exchange, games, flash cards etc

Classes I find will be the most productive example, especially if it's with a Native speaker. Generally mixing everything together there would be the most ideal but even getting a Hold of a good Audio Book, workbook & phrasebook and using online resources would be ok.

wow, thanks for the language exchange. It's amazing to be able to actually voice/email chat wtih someone and help them learn english :O

i ever learn jananese about two monthes when i am in shcool,but i am not insist on learning it.now i think it is really pity....

You can learn Japanese using intranet...there are lot of website which are very helpful for learning japanese. try it...