March 4, 1998; Hecht said, "For me, this building is the physical manifestation of a personal dream, which is that when people think of cartoons, they'll say Nicktoons." In June 1997, Nickelodeon began a five-year, $350 million investment into original animation. As part of this effort, the company doubled its animation staff and produced many new pilots, including one for SpongeBob SquarePants. Before commissioning SpongeBob SquarePants as a full series, Nickelodeon executives insisted that it would not be popular unless the main character was a child who went to school, with his teacher as a main character. The show's creator, Stephen Hillenburg, recalled in 2012 that Nickelodeon told him, "Our winning formula is animation about kids in school... We want you to put SpongeBob in school." Hillenburg was ready to "walk out" on Nickelodeon and abandon the series, since he wanted SpongeBob to be an adult character. He eventually compromised by adding a new character to the main cast, Mrs. Puff, who is a boat-driving teacher. Hillenburg was happy with the compromise and said, "A positive thing for me that came out of it was [how it brought] in a new character, Mrs. Puff, who I love." According to Nickelodeon writer Micah Wright, the series pickups for both SpongeBob and CatDog were announced on the same day in 1997. Nickelodeon's senior vice president, Kevin Kay, confirmed to the animation studio's creative team that it had greenlit 100 episodes (200 individual segments) of CatDog and six episodes (twelve segments) of SpongeBob. Nickelodeon believed CatDog had the potential to be its next breakout hit, and their order represented an investment of $50 million into the series alone. Stephen Hillenburg was doubtful that his show would last, and he stated in 2009: "I was thinking if we could make a pilot, then we'd have one episode and have accomplished that. Then I thought if it did go to a full season that we'd get twelve chances to write stories and that might be it... that we'd make twelve shows and get cancelled." In 1998, Nickelodeon premiered Oh Yeah! Cartoons, which was intended as a "character laboratory" to test out cartoon characters. Creator Fred Seibert described the show as an experiment into a seven-minute format that Nickelodeon generally avoided; he said, "they were very willing to try an experiment to see how it would work." The series eventually yielded three half-hour spin-offs based on