A 3-page Slicer mastery project for 7th-grade geometry. Students act as 3D Imaging Technicians, building physical models of solids (clay or digital) and performing "scans" (slices) to identify and calculate the area of internal 2D cross-sections. Includes a detailed lab protocol, imaging log, and the "Slant Challenge" visualization task. Content updated to hit 3-hour duration and fix missing solid (Triangular Prism).