The colorful animals in this rounding card sort will motivate even the most reluctant students. First, students will round each number on each animal card to the nearest 100. Then they place each animal under the corresponding zoo gate. This product was designed to meet the 3rd Grade Common Core Standard 3.NBT.1, but can be used in other grades for a challenge or review. These task cards can be a cooperative group activity, an early finisher activity, or an assessment.