And with their school allotment, pupils at Oliver Quibell infants in Newark, Nottinghamshire, have all three in abundance.
Mrs Curtis, a keen gardener, leapt at the offer from the local council to look after a full-size plot just 250 metres from the school. Pupils grow seedlings in the classrooms, transplant them into the allotment, tend the garden during the growing season and then harvest the fruits of their labours.
Over the past four years they have grown and eaten cauliflower, beetroot, carrots, beans, cabbage, soft fruit, salad, herbs, tomatoes, peppers, cucumbers and pumpkins. In summer, each of the 130 pupils, aged four to seven, has at least an hour a week at the allotment planned into their schedule.
And in addition to PE sessions, a class might start with a mini-aerobics session or a fast walk round the school grounds.
Mrs Curtis said: "We want to show that exercise and healthy eating can be an inexpensive part of everyday life."