Activity 1 — Rainbow Chromatography (Science/Chemistry, 20-30 min) Coffee filters + washable markers + water = instant rainbows and a sneaky lesson on pigment separation, mixtures, and solvents. Black markers always steal the show! Activity 2 — Lucky Bridge Challenge (Engineering/Physics, 25-35 min) 10 sheets of paper, a little tape, two stacks of books, and suddenly your students are structural engineers. Accordion folds, compression, tension, and a whole lot of coin-stacking suspense. Activi