Computers break down. There are problems with technical support, especially in primary schools. Computers distract students from the lesson at hand. Computerised education is driven by the self-interest of industry. Children need a broad base not a one-dimensional computer.
Computers discourage children from linking ideas.
Computer screens flatten information into narrow, sequential data. The mediated world is less significant than the real one. Computer users grow rusty in their ability to think. Computer skills are not very useful for employment. Business dominates software and other curriculum material.