Tring School in Hertfordshire said the laptop devices will be brought into use from next year.
But more than 100 people have signed an online petition against the plans.
Headteacher Sue Collins said the school was having to manage an £800,000 per year cut in its budget from the government.
The Chromebooks for Learning Scheme will affect hundreds of students at the school, which has more than 1,500 pupils aged from 11-19, with only years 11 and 13 exempt.
There are two options available, a £149 model and a £185 model, although pupils from disadvantaged backgrounds can pay £20.
The school said students "need to be prepared for an increasingly digital world".
It is offering payment plans, but many parents and pupils said the devices should be provided by the school.
The petition's organisers said people were being forced to pay when there were "perfectly good computers at the school".
Ms Collins said she "wholeheartedly accepted" parents concerns but insisted the school was having to manage a budget cut.
"It is absolutely enormous to manage that and at the same time raise standards and continue to develop so that our children have access to the online and modern materials that are out there now," she said.
"There isn't a U-turn on this, we're rolling it out. We know from the research we've done, this is the way forward for schools."
A secondary school has ruled parents must pay a compulsory charge of at least £149 for pupils to use Google Chromebooks in lessons.