Abstract: An instrumented, adjustable, educational, structural model employs novel sensor housings and free-fall, pendulous, and cantilever-beam test objects made of stiff, hard, compressible material, for calibrating accelerometers; for demonstrating behavior-testing and health-monitoring machinery technology; and for exploring the radiant, vibrant, automatic, communicative nature and behavior of energetically interacting things. Unusual tests confirm Newton's Laws of Motion, and how energetic interaction causes things to happen and move. Somewhat surprisingly, sensor signals faithfully track the arcing motion of a glider type swing, but not that of a simple pendulous swing. Resulting from a dimensional interference fit, residual stresses in the compressible housing of a plug-in, motion sensor accurately align, secure and intimately clamp together imperfect mounting surfaces; and facilitate sensor assembly without the use of adhesives.