In my experience Indians are a lot more willing to commit to long-term, difficult projects at the urgings of elders. But they share that with other Asian cultures. This also helps explain the spelling bee thing; Indian families are used to the idea of rote education being very important, and even participating in the education of their child that way. Really, almost anybody can get that good at spelling, it's just that more European-American parents would tend to see it as pointless.
The one thing I do find interesting is how the gender split works. Asian minorities (in the American sense: China, Japan, SE Asia) seem to have very different expectations of boys versus girls. But modern Indian families, from the castes that are likely to produce US-bound immigrants, seem to encourage their daughters to go for technology jobs. For me at least, almost 100% of the female engineers I've worked with in the Valley were Indian-born.
And the other thing I've always found strange: the QA departments of many companies in the Valley are dominated by Indian-born women.