>>Children of teen mothers do worse in school than those
>>born to older parents. They are 50 percent more likely
>>to repeat a grade, are less likely to complete high
>>school than the children of older mothers, and have
>>lower performance on standardized tests.
>
>You should be very careful in drawing any conclusions here. The correlation between the two might be statistical fact, the cause is little trickier.
>
>On one hand you could think that kids are not raised in an optimal way by their teenage mothers, OTOH, it could also be that the typical teenage mother is less talented than average and passes her genes to her kids.

The explanation may be simpler - the teenage mothers surely lack the accumulated wisdom and experience that the older parents have, on the average. They, therefore, have less of it to pass on to their offspring. This includes their own attitude towards education and knowledge as well. Some of it may actually be the cause of their pregnancy in the first place, which may be a vicious circle by itself.

IOW, it is passed to the next generation, but not necessarily by genetics. Could be sheer mentality and attitude.