To me the solution is: Ban homework. All projects, essays, tests, etc are done at school on air-gapped machines or written by hand. Work is monitored by the teacher with video surveillance in 'test halls'. Cell phones can be kept in a small locker. If the student needs to be reached, a parent or whomever can call the school. Internet research should be done in a separate environment, printed out, then taken to the 'work' location. Like how you used to photo-copy sections of a book. Printed text can be cataloged by the school and compared to completed work for plagiarism.
Take away the internet. Except in a research/library scenario. Give them a limited time to complete tasks. This would promote a stronger work ethic, memory/recall and more realistic to time management skills. They need to learn to rely on themselves, not technology. The only effective way is to remove tech from the equation, otherwise the temptation to cheat to compete/complete is too strong.