In this video I show you how to make a Door Alarm Model science project using a simple magnetic door security alarm concept. The idea is very easy for school—when the door opens, the circuit changes and the buzzer gives an alert, just like a door open detector. I made the full model using cardboard and color paper for the outer body, so it looks neat for exhibition, and inside I used basic electronics like 9V battery, switch, connector and wires. I focus on making it simple, low-cost, and working properly, so any student can build it at home. This project can be used as a school door alarm system, classroom door alarm, or even as a touchless/automatic doorbell-style demo depending on how you place the magnetic contact. My main takeaway for you is: keep the wiring clean, fix the parts strongly with hot glue, and test the connection again and again before final decoration. If you want a smart-looking security alarm model for your science fair, this is a very good working model idea.