Oh, of course you're not pushing! You're running along behind trying to keep up! I think everyone here recognizes that. Many people here are running right along with you!
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One concern I have is to have him finish formal high school studies and have little or no academic work going on for the next 7 years or so and then trying to apply for these programs. Does that make sense?
Definitely, it does! Oh yes!
But I do think it's possible--albeit challenging--to balance some more unusual academic subjects with some more traditional ones or to dig more in depth into traditional subjects and slow things down a bit at the high school/college level. I think moderating speed through lateral thinking is harder to do at the elementary/junior high levels than it is to do as kids progress. Other than problem solving and word problems, how do you go deeper into addition and subtraction or handwriting? Speed is just about all you have to get past the "easy stuff" and finally get to work that requires real thought. But you can do more with calculus or science experiments or argumentative writing at the high school level. There are lots of books to read and papers and stories to write and mathematical and scientific puzzles to solve.
I guess what we're planning to do when we're in your shoes (and I thank my lucky stars that we're not there yet!) is to seek out ways to broaden and deepen our child's educational experience. I think it's easy to get into the "This is what you study in high school and then you're done" mode of thought, when that's not necessarily required, just traditional. Thinking creatively about other academic topics or disciplines or uses of his time than "the usual suspects" might keep your child moving forward without having to go off to college too soon.
I'm on my first cup of coffee today, so I'm not sure I'm making sense...
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Does that follow?