Give them $100 and a new Suit and send them home with their parents
The reality is that these Dreamers have been given SSNs, work permits, and in many cases driver's licenses depending upon the state. It will be very difficult to reverse it without a huge public fallout. Most of the public have swallowed the narrative of poor children being brought here by their parents. The law states that you just have to be here prior to age 16. It doesn't matter if you came here with your parents or arrived unaccompanied.
I can see Trump terminating the program immediately so no new "Dreamers" can be legalized. Since the DACA cards must be renewed every two years, he can say that at the time of renewal, the applicants will be fully vetted and then a determination will be made on an individual basis of whether you can stay here or not.
Obama's ICE also did not go after the illegal parents of DACA Dreamers. The parents were exempted from removal. That can stop immediately as well.