Pupils at nearly 100 schools across Oxfordshire, Berkshire, Buckinghamshire, and Hampshire will be taught how to carry out CPR and use a defibrillator.
The training will take place as part of Restart a Heart Day on October 15, delivered by teams from South Central Ambulance Service.
The ambulance service is aiming to train more than 10,000 pupils in how to respond during a cardiac emergency.
South Central Ambulance Service will teach CPR to children across Oxfordshire(Image: SCAS)
David Hamer, paramedic and operations manager at South Central Ambulance Service, said: "Restart a Heart Day is one of the most important dates in our calendar because it's about giving thousands of young people the skills and the confidence to save a life.
"We are incredibly grateful to our community first responders, co-responders, and South Central Ambulance Service staff who are volunteering their time to visit schools across our region.
"Without their commitment, this huge training effort would not be possible. Together, we can give more people the chance of surviving a cardiac arrest."
The sessions will focus on how to perform chest compressions and using a defibrillator.
Each year, nearly 30,000 people in the UK experience a cardiac arrest outside hospital and receive treatment, but fewer than one in 10 surviving.
Survival chances decrease by 10 per cent for every minute without CPR or defibrillation.
Restart a Heart Day is part of a worldwide initiative led by the Resuscitation Council, British Heart Foundation, St John Ambulance, British Red Cross, and ambulance services across the UK.