I am not american and never heard about a "black college" before. Are those words (along with the TCUs you mentioned) used for historical reasons, or is there still segregation (wether legally or de-facto)?
The meaning of my second question was actually that I disagree that "beefing up the Computer Science programs in black high schools" will help much beyond a little short term relief. Efforts should focus about understanding and fixing the systemic problems, not the symptoms.