"Students using tablet computers at school saw on average a 10 percent
lower math test score versus peers who didn’t. E-book reader use meant
an 18 percent lower score in reading. Desktops, laptops, internet access,
and Wi-Fi all were linked to lower scores. Even the widely touted
interactive whiteboard was associated with worse results in reading,
science, and math. The only technology linked to a meaningful
improvement in test scores was that old standby, a projector."
— Rotten STEM: How Technology Corrupts Education

projectors are the only meaningful edtech hardware
Andrés Cuervo