"Second, it harms students even in the narrow sense of training workers: the use of technology in schools actually lowers test scores in reading, math, and science, damages long-term memory, and induces addiction. Both advanced hardware and the latest software have proven counterproductive. The only app or device found to meaningfully improve results with any consistency is an overhead projector in the hands of a competent human teacher."
— Rotten STEM: How Technology Corrupts Education

projectors are the only meaningful edtech hardware, pt. 2
Andrés Cuervo