Let me tell you something. Many years ago, in 1985, I was working with a private student who was failing ninth grade math. He didn't even have the basics that were taught at the middle school level. As the time for the regents approached I got copies of every algebra regents I could get my hand on. Some of them went back to the 1950s.
Do you have any idea how many times the question on how to factor x^2 - 100 has come up? Any idea how many times they have asked for x^2 - 25? Over and over and over again.
The same holds true for other problems. The numbers may change, but the formats are almost identical. You can find problems that are identical if you go back far enough. And by repetitive practice using all these regents, my student, who the school wanted to put into special ed, who the teachers had basically written off, not only passed - he did so with a 92! If that wasn't enough - we did the same thing for biology (now called Living Environment) and found the same pattern. This resulted in passing grade of 88. Pretty good results for a kid who didn't know enough to generate a 30 on either regents prior to April.
The more regents you do, the more comfortable the students become, and better the chance that they will recognize some of the problems they see. Confidence breeds success!