Assess students' ability to analyze how a per‑unit tax, a subsidy, and a binding price ceiling affect supply and/or demand in a local lemonade‑stand market: identify which curves shift and why, predict changes in equilibrium price and quantity, estimate impacts on consumer surplus, producer surplus, government revenue and deadweight loss, and explain who wins and who loses (consumers, sellers, government) using simple graphs or numerical examples. Designed for grades 6–8 with advanced problem‑solving and explanation tasks.