Your family should think carefully about your overall plans for immigration. If the plan is for the entire family to settle permanently in the US, then your son should study here. It will be much easier for him to find a job in the US with a US degree, and there will be no worries about losing his green card status.
How good is your son’s English? Perhaps he could enroll in an intensive English course here for a semester or a year while he looks for good places to complete his undergraduate degree.