how is scoring a 2050 on sat's in 8th grade?

For one, that adds up to 2030, not 2050. Nitpicking aside, that's an excellent overall score, but you should really try to balance that out (540 vs. 800 is something colleges dislike). By junior year you can aim for 2200 above, as long as you improve your writing and reading.

Starting from a base score of 2030, I would expect at least a 2200 if not higher when you're a junior. The main concern is that as you progress in math, you will start getting away from the Algebra and Geometry that you're probably good at now because you're learning it right now, so that you'll start forgetting parts of it. I would expect your Critical Reading and Writing to increase naturally, enough so that it would compensate for the fall in Math, but it's something to keep in mind when you get around to studying for the SAT when you take it in 11th/12th grade.

Wow that's excellent for an 8th grader. for math you must stay careful and remember the old stuff. Reading is solid already to be quite honest. Writing you just have to learn 5-6 big rules of grammar and you can easily get around a 700. I can see you getting a 2200-2300 easily by junior year. Great start. I think I can see: 800 math, 700 reading, 700 writing. that's 2200. or if your reading gets to 750, a 2250. Great start. you're already quite ready for college : D