I do not know all the details about this current cheating scandal, but having taught in three different districts, I can tell you this:  If more attention is paid to test scores than to students, then something like this is bound to happen.  If teachers are under the impression that they are to teach to the test and are paid on the results of test scores, this will happen.  It's like being paid on production.  If so many seams have to be stitched, then no one pays attention to the whole garment until the end of production.  If something is wrong on one seam, the whole garment does not pass inspection.  Likely in education, if one test is important, the "human garment" will not pass inspection.  Teachers don't just teach a subject; they teach students.