Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking dish.

Beat cake mix, water, oil, and eggs in a bowl using an electric mixer on low speed for 30 seconds. Increase speed to medium and beat for 2 minutes more.

Pour batter into the prepared baking dish.

Bake in the preheated oven until a toothpick inserted in the center comes out clean, 28 to 33 minutes. Remove from the oven and cool completely, at least 1 hour.

Crumble cooled cake into a large bowl.

Stir frosting into the crumbled cake until mixture is sticky and starts to come together but is not too smooth. Refrigerate until chilled, for at least 30 minutes.

Roll cake mixture into eighteen 1 1/2-inch balls and place on a baking sheet.

Place about 1/4 cup candy melts in a microwave-safe bowl. Microwave on high until melted, about 20 seconds.

Push a lollipop stick halfway into each ball of cake mixture.

Gently dip balls into the melted chocolate to coat, then place upright in a block of styrofoam.

Decorate with candy sprinkles while chocolate coating is wet. Repeat to make remaining cake pops, melting more candy melts as needed.