The Scare (aka Friday the 13th) - S1-E11
Plot hole: When Pacey drives them all to the market, he explains that he had to 'steal' the car from his family, and thus doesn't have the keys. He makes Joey stay in the car while they are shopping, because he can't turn off the car. But later, at the end of the episode, Pacey suddenly goes running out of Dawson's house late at night, jumps into the same car and turns keys in the ignition to start it and drive off in a hurry. How would he suddenly have the keys to the car? He drove them all straight to Dawson's house from the market, with the crazy girl - and the car had been there ever since. He had no time to go back home to get the keys; and it isn't likely his father, the town sheriff, would allow his underage son without a legal driver's license, to have the keys.
Answer: It's only explained once in the series. Jack says to Andie "I tried to start kindergarten without you", meaning Andie was smart enough to start school early.