Baltimore cannot be the only place that does that, not by a long shot. I think this has likely been going on with many many schools for many many years. I graduated in 1978 from HS in Sioux Falls SD, I was an average student at best,not a great student, but mostly solid B's with a few A's and a couple of C's sprinkled in, somehow I managed to avoid getting D. All of my C grades were geometry, trig and algebra which I did struggle with and had little to zero interest in. Even back in the years from 74 to 78 when I was in school I never knew of a single kid who did not graduate, there were always a few who had D'd and F's in every class , but somehow they passed and got that diploma. Grades had to have been changed for that to have happened. My parents who graduated HS in the mid 50's said that it was not uncommon for kids to be held back to repeat a grade, or if in HS have to attend summer school after the rest of the class had graduated and they would not get to walk across the stage and they would have diploma mailed to them after passing summer school. My dad said it was known as "summer bummer" Schools do not hold kids back or send them to summer school any more.everybody passes and with each grade they fall farther and farther behind. I am guessing that this practice of passing everyone started back in the 70's. The teachers and principles will not come out in public and say it, but the reality is everyone passes, at least at public schools.. private schools are probably a different story.