AS you mentioned, factors that contribute to intelligence include their home environment and parenting, education and availability of learning resources, and healthcare and nutrition. But the existence of knowledge in applying response and application of the desired feedback is only communicable by learned process. The factors you mentioned are part of the learning, not an inborn capacity.
Using the alternate to positive learning like your ghetto moms’ actions is an example of learned helplessness. Learned helplessness occurs when an individual continuously faces a negative, uncontrollable situation and stops trying to change their circumstances, even when they have the ability to do so. And that, when done at an early age, causes a lack of the child gaining influence of learning and falling behind rapidly.
So besides the desire to improvement, which is done by learning the tools to use in the determination of intelligence capacity and the success it displays if only for the self esteem of the student, it creates a self destructive attitude that further hampers the ability to survival. And that is apparently being determined at colleges for their use in entrance. So the student being not capable to advance was determined a long time before that by both atmosphere and tool learning. The testee may be incredibly intelligent. But without the tools to use, it can impact their ability to use that intelligence.
wy69
Verbal skills, so called crystallized intelligence or product intelligence can definitely be influenced by environment. But not past what nature has apportioned, only maximized.
Nonverbal abilities, so called fluid intelligence or process intelligence is hard wired and not generally amenable to increasing in any sense.
Young students from deprived background/neglectful families and environment can often score average in nonverbal intelligence but low average in verbal intelligence. For example a nonverbal IQ of 100 but a verbal IQ of 85. The verbal scores can be improved with intensive verbal training but nothing will take you past what nature has given you, only maximizing what you have.
By the time kids are about 12 or so, the scores are generally fixed and not changing.
The moral of the story is work with your children with precise exacting reading, verbal language and talking to develop and maximize their abilities. You cannot move past what nature has given you, only maximize it, but you can definitely retard what was given you by neglect.