Why do some demographic groups in America succeed while others fail? any ideas would be appreciated?

Answer 1

To answer that question, you need to do two things:
1.) Define success, and
2.) Find the factors that help increase the likelihood of success.

For example, if you note that a two-parent household, full access to education, and economic security make a child more likely to be successful, then it shouldn't surprise you to learn that Blacks are less likely to be successful than Whites, given that they are less likely to have economic security, a two parent household, and to a lesser extent, full access to education (Note: Some of that access is self-limited, i.e. the youth feels education is unimportant, and does not pursue it).

From those two things, you find a two part answer:
1.) The demographic group has an inherent social or economic barrier to success (i.e.: the poor, or perhaps a demographic group that is officially discriminated against, such as blacks in Apartheid South Africa or the US before the 60's)
2.) The demographic group is more likely than other groups to have social or economic barriers to success (i.e. Blacks and Native Americans in the US).

Answer 2

Read "Lies My Teacher Told Me" and "Guns, Germs, and Steel."