Learning goals: Teacher Facing Compare, contrast, and critique (orally) different strategies for determining the area of a triangle. Generalize a process for finding the area of a triangle, and justify (orally and in writing) why this can be abstracted as $\frac12 \boldcdot b \boldcdot h$. Recognize that any side of a triangle can be considered its base, choose a side to use as the base when calculating the area of a triangle, and identify the corresponding height. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from 6.1 Area and Surface Area, Grade 6.