Megan wins the lottery and goes on a mad spending spree. Mum, trapped in Megan's body, learns what it's like being a child with two paper rounds, no money and peer pressure.

Megan is in the doghouse after parents' evening, and to make things worse her little brother Freddie has won a class trophy. When he is also chosen to star in the school promo video, Megan decides to run away because no-one appreciates her.

Megan is terrified that she and Freddie will be pushed out when her dad announces he is marrying new partner Sabrina, and does all she can to sabotage the wedding.

Megan starts a freedom strike in school after finding out her mother has a new job in London, and has put the house up for sale, without telling her.

Megan has a crush on a sixth former and Margaret has a crush on her dance teacher. However in order to impress the men they like, Megan and Margaret must once again swap places.

Chaos descends when Megan's glamorous gran Marlene comes to stay after Margaret breaks her leg.