Thanks for your question!
There are currently 18 houses, each with over 100 levels (and each of those with multiple rounds)! This is in addition to regular live events, holiday promotions and much more!
We're always working on new content for the game, including new houses, themes and recipes! As you can see from the house selector menu at the bottom of the Family Planner screen, the next house is coming soon. Please follow our official Facebook page for news, contests and much more:
https://www.facebook.com/pages/category/App-Page/Virtual-Families-Cook-Off-268634747356498In the meantime, you can also go back and replay any levels in which you haven't collected all of the pins! Once you've collected all of the pins, you'll notice picture frames appearing - these are Memory Levels that allow you to endlessly replay!
We hope you continue to enjoy cooking with your Virtual Families!