should i take a Japanese course this summer, or next year in school?

I would suggest starting as soon as possible to learn a new language. If you are planning on gaining 2 years of knowledge in Japanese, then I would suggest starting a course during the summer to gain 1 year's worth of knowledge, since you might have more time right now than your junior year which is said to be the busiest year of high school. If your school allows it, then take the test to skip first year of Japanese, and take Japanese 2 during your junior year. If this doesn't work out, then continue taking online courses or private lessons for Japanese outside of school in a series. I would say that taking Japanese only during the school year might not be good enough to reach your goal of learning 2 years' worth, so it's best to do self-paced courses and take lessons (school or any outside tutor) in any format. Hope this helps!

Hello! I'm a rising 11th from Japan! Yes. The more experience you have, the better. If you're seriously considering moving to Japan in the future, it would be beneficial to understand Japanese culture and language. Especially, since you will come from a foreign nation, it is very appreciated that you actually put effort to try to support Japan. While there may be no direct correlation between the amount you studied vs admiration, it would help if you understood the language even a little bit more than now (unless you're extremely good even compared to native speakers). That's just my personal opinion though, so take it lightly.

勉強頑張ってね。

SilverDragon (Class of 2025, 10th-Rising 11th, Japan)