This resource guides students through the process of subtracting a larger number from a smaller one while encountering zeros in the minuend. It emphasizes regrouping, explaining how to handle zeros in different place values and provides detailed steps for visualizing the subtraction process. It includes alignment tips, common pitfalls to avoid, and offers practice opportunities to reinforce understanding. The document describes the 'Zero Obstacle' students may face, outlines a step-by-step approach to regrouping, and encourages verification of answers through addition. It culminates in practicing a subtraction problem with a whiteboard challenge to solidify the concepts learned.