The three-dimensional currency demonstrator with magnetic induction is designed for middle school physics teaching. It visually represents the direction of the magnetic field at different points in the space around a magnet, shows the formation and orientation of magnetic flux lines, and displays the magnetic field on the induction wire. Components - Band magnet - Latch magnet - Six rectangular transparent magnetic induction plates - A crescent transparent magnetic induction plate - A fixed holder How to use - Shake the demonstrator several times during the demonstration to cause the small pieces of iron to appear irregular. - Pull out the movable plate in a semicircular arc, insert the cross-shaped magnet, stick it to the surface of the plate, and tap lightly. - Magnetic core currency appears in a magnetic field. Purpose - Demonstration experiment to explain the existence of a magnetic field and the spatial distribution of magnetic field lines. Use scenarios - Classroom demonstrations in middle school physics to visualize magnetic field direction and flux patterns around magnets. - Science lab sessions to illustrate magnetic induction and the arrangement of magnetic field lines. - Educational displays or science fairs to communicate fundamental concepts of magnetic fields to students.