They are already a captive audience. Present a monetary benefit. Some are leaving for year 2K culture go back to family, financial incentive doesn't work to deter them. Employees came here to improve family condition. Not learning english can hurt children more more disciplinary problems.
Spanish parents teach other parents.
This helps children to end up in a successful job but some have illegal alien parents. These children can't work. J. Getting children earlier makes it easier to steer them in the right way for a better integration into society. Upcoming generations have more potential of integration to achieve a bilingual community. Some parents don't know or are last to know what their children do.