Pokemon Best Wishes! - episode 12 - 08 Dec, 2010

On their way to Nacrene City, the gang is harassed by a group of schoolchildren with the Garbage Pokémon Trubbish. They head to a nearby Pokémon Daycare and kindergarten, where they learn from the kids' teacher, Ms. Daniela, that the kids found the Trubbish at the garbage dump and decided to bring it back to the school against her orders. Ash later challenges Ms. Daniela, and wins, earning a Pokémon Egg. Elsewhere, Team Rocket is given a fake meteorite from Flint and are told that they will get more information later. (Source: Wikipedia)