Floating Pin Challenge

Description

It includes the student investigation, prediction questions, variables, materials and safety, step-by-step tissue-paper method, repeated-trial results table, analysis questions, surface-tension explanation, detergent extension challenge, and a teacher guide with suggested answers and troubleshooting tips. I also refined the science: rather than describing surface tension literally as an “invisible skin,” the teacher notes explain it through cohesive intermolecular attractions and distinguish surface-tension support from ordinary buoyancy.