This learning resource focuses on enhancing students' subtraction skills, specifically in calculating the difference between two multi-digit whole numbers using the standard subtraction algorithm, emphasizing the necessity of regrouping. The task involves a real-world scenario with two herds of elk in a national park, allowing students to apply their subtraction skills to find the difference in their populations. The resource also includes a confidence check for students to self-assess their understanding of the regrouping steps, a challenge question to promote critical thinking about how additional numbers affect the difference, and reflective prompts to encourage metacognitive thinking about their learning process and strategies employed during the task.