Pink Pearl erasers were the original! Every year, I would have to buy one new pink eraser for school (the school listed Pink Pearl erasers specifically). And sometimes in the classroom, the teacher would cut the little bars in half to make the erasers last longer. For days after acquiring a new eraser, I would try to use only the edges and as sparingly as possible — an attempt to save its pristine state. But after the necessary had happened and the eraser was grey and bruised, I would anxiously try to use as much of the eraser as possible, using every opportunity as work toward the chance to buy a new one.
Magic Rubs were, of course, the upgrade. While the white rubber bars lacked the same satisfying pink color as Pink Pearls, Magic Rubs would erase beautifully. Where Pink Pearls would have worn away the paper from feverish erasing, Magic Rubs would sweep away any graphite accidents with satisfying grace.
Ah, the days when all was pencils, erasers, and pencil boxes.