Build your own Birdhouse Kit, Teachers, this is a great and affordable way to get your kids Design, Building while creating something practical and at the same time beneficial for the environment, Perfect size for a chickadee or finch, Comes unpainted, Assembly required
Balance kit, package includes an air core solenoid and a current balance for demonstrating and measuring the small force experienced by a conductor carrying an electric current in a magnetic field, one half of the current balance is placed inside the solenoid