For the finale, Valerie Bertinelli and Duff Goldman focus on biomes -- large regions of Earth with specific climates that are home to certain types of living things. The three final bakers must make cakes based on a specific biome: rainforest, desert or coral reef. The young baker with the best biome cake earns $25,000 and the title of Kids Baking Champion!

Why have one kind of pie when you can have two? Valerie Bertinelli and Duff Goldman task the four young bakers with creating a two-flavor sheet pan pie. Successfully making two different delicious pie fillings and a tasty crust plus great decorations will land three bakers in the finale.

In the cookie face challenge, Valerie Bertinelli and Duff Goldman challenge each of the five bakers to create a giant cookie face with 3-D features that communicate an assigned expression like happy, sad, angry, surprised or excited.

The competition has gone to the dogs! Supercute puppies, to be exact. To celebrate Puppy Bowl on Animal Planet, Valerie Bertinelli and Duff Goldman pair each of the six bakers with an adorable, adoptable puppy and challenge them to create a cake that reflects their puppy's happy life after adoption on his or her first birthday.

Desserts get a balanced hit of sweet, savory, bitter and sour from Chinese five-spice powder, which is a mix of star anise, Szechuan peppercorns, fennel, cinnamon and clove. For this challenge, Valerie Bertinelli and Duff Goldman ask the seven young bakers to create Chinese five-spice desserts to stay in the game.

Valerie Bertinelli and Duff Goldman love picnics, but desserts don't always fit into a picnic basket. They challenge the eight young bakers to create portable hand pies and a dressed-up version of "ants on a log."

It's the most-anticipated challenge of the competition -- dessert imposters! Valerie Bertinelli and Duff Goldman challenge the nine kid bakers to create breakfast, lunch and dinner imposters.

What's that beautiful arc of color in the sky? It's a rainbow! For this challenge, Valerie Bertinelli and Duff Goldman task the 10 young bakers with working in teams to create vibrant and dazzling cupcake rainbows.

Garden-themed decorating is gaining in popularity, so Valerie Bertinelli and Duff Goldman challenge the 11 young bakers to create garden cakes decorated with actual fruits, herbs and other natural ingredients -- no glitter, sprinkles or fondant allowed.

Hosts and judges Valerie Bertinelli and Duff Goldman embrace the brushstroke decorating trend by asking the 12 young bakers to create colorful and delicious brushstroke mini cheesecakes.