Comcast is offering $10 a month internet service for low income families. My guess is that the marginal cost of adding one more internet line is close to $10. To verify that families are low income, their children must be enrolled in reduced/free school lunch program. This helps Comcast prevent high income people from enrolling.
Comcast didn't do this out of the kindness of their own heart, instead it was required as part of the governments stipulations for Comcast buying NBC. PC World also has a good rundown of the pros and cons of the merger. To outweigh some of these cons home internet for disadvantage children seems like it could be a public good.