She always acts like a goody-goody, but I know she's not as innocent as she seems.

She is such a goody-goody.

She always acts like a goody goody, following all the rules and never getting into trouble.

She is such a goody goody, always following the rules.

The goody-goodies always follow the rules and never get in trouble.

The goody goodies at the party were all dressed in their best clothes.

The goodie-goodies were excited to receive their rewards.

She is often seen as a goodie-goodie because she always follows the rules and never gets into trouble.

Her goody-goodiness was evident in everything she did.