Answer:
Ender isolates Bean from the rest of the group. He kept telling the others that Bean is better than them and making the other kids hate Bean. He also taunts Bean and makes fun of him. Just because Bean is smarter than the other kids and has more potential, Ender points it out and makes the other kids target Bean. This happens with Ender when Colonel Graff makes the other kids in his launch group hate him by pointing out that Ender was smarter than them.
Bean is the smartest of the kids and Ender decides to isolate him to make him better. Ender knows from his own isolation that it has made him more independent, a better commander, and a better problem-solver. He wants to sharpen Bean’s wits; intensify his effort; keep him off balance, never sure what’s going to happen next, so that he always has to be ready for anything; ready to improvise; and determined to win no matter what. However, Ender knows how painful it was for him during his isolation which makes him more compassionate to Bean then Colonel Graff was to him.