My son (now 18) was a bright and happy student. Until a first year teacher attempted to teach cursive writing in 2nd grade. It made him feel like a "bad" student and he never recovered. We still hope he'll graduate, either 2010 or 11, but years of thinking of himself as a bad student has really taken a toll. His standardized tests scores show he's more than competent. But his handwriting is so bad, he just stopped turning in homework.
Remember -- only 10% of anything can be in the top 10%.