Prepare the white cake batter according to the box instructions. Combine two boxes of batter in one bowl, and prepare the third box separately in another bowl. Into the bowl with the single box of batter, stir in ½ cup of strawberry jam until fully incorporated. Prepare your cake pans by greasing, flouring, and lining them with parchment paper to prevent sticking. Pour the plain white cake batter into two of the pans and set them aside. Pour the strawberry-flavored batter into the third pan. Bake all the pans together according to the directions on the box.
Once baked, allow the cakes to cool for at least 30 minutes; placing them in the freezer can speed up the cooling process if needed. On a flat surface, take one white cake and the strawberry cake and slice off their domed tops to create flat surfaces for stacking.
Take the third cake and crumble it into small pieces to prepare for cake balls.
Add ½ cup of vanilla frosting to the crumbled cake and mix until it forms a moist, dough-like consistency. If the mixture is too dry and the balls don’t hold together, add more frosting until the desired texture is achieved. Chill the cake balls in the refrigerator. Place one of the flat white cakes on a cake stand and cover it entirely with vanilla frosting. Spread a layer of strawberry jam over the frosting, then sprinkle crispy cereal evenly on top of the jam. Carefully place the strawberry cake layer on top, aligning it evenly. Next, frost the upper half of the cake using the strawberry frosting, blending it slightly with the vanilla frosting in the middle to create a gradient effect from light pink to a deeper pink on top, fading to vanilla at the bottom.
Crush some strawberry cereal and sprinkle it over the top and around the edges of the cake.
For decoration, take the chilled cake balls and coat them with sprinkles. Arrange these cake balls around the perimeter of the cake. Break the strawberry Pop-Tarts into pieces and stack them on top of the cake, nestled between the cake balls. Finally, place the strawberry Pocky sticks along the cake’s edge, positioning them between the Pop-Tart pieces and the cake balls for a fun and colorful finish.