A mechanical digger has begun tearing down the old St Peter Port School.
The Les Ozouets campus was built in the 1960s.
Specialist contractors have been removing asbestos, and now a mechanical digger is being used to break the building down.
The site should be levelled by mid-August, to allow a new Guernsey Institute to be constructed.
Institute Head Tracey McClean says the new campus will offer opportunity to many post 16 students:
"In three years time hopefully we will be moving into a brand-new building, so it will mean that we can increase our provision and opportunities on the island.
There's nothing like learning in the classroom and being with a group of peers and sharing ideas."

Alderney enjoys a Royal Visit for the 80th Homecoming anniversary
Exhibitors finalised for first Guernsey travel show
WATCH: Last Blue Islands plane leaves Jersey
New woodland for Alderney's 80th Homecoming
Guernsey States 'in talks' with easyJet
Guernsey's airline Aurigny takes on six new First Officers
Call for more transparency over Guernsey Electricity's charges
Guernsey Police investigate 'unexplained death' in St Peter Port