"This is the right thing to do because it makes so much more sense for children and also for people working in the services," he says. Nationally, the change will take about five years, he believes, but "the real revolution is about people's thinking". Heads who have not yet begun working this way will be in for a shock. Running a full-service school demands "a different type of leadership". There is more partnership, less command and control.
Although most heads and teachers agree in principle with the idea of working more closely with other services, and recognise benefits for children and families, there are also worries, about losing autonomy or having extra work to do. It has taken about 18 months for nearly everyone to embrace the inclusion agenda, says Mr Hawker.
For teachers, it means they are part of a bigger service, so they need to understand (but not do) the work of others, such as social and mental health workers.
It means teachers will know where to turn with their concerns about a child, and should get a quicker response from people such as developmental psychologists or other health specialists. Teachers will also have some training in child protection, so that they feel more confident about knowing what to look for and when to alert social services.
"Child well-being is actually about teachers having wider networks to link into," says Mr Hawker who points out that Dave Pelzer, the author of The Child Known as It, who suffered terrible abuse and torture at home, was saved by teachers from being killed .
Education has already been merged with social services at Brighton and Hove and health will follow, as the Children's Trust - the independent committee managing children's services - gets under way. Education is still by far the biggest component, with teachers outnumbering social workers 20:1.
"It's about all of us learning to work differently and in partnership," says Mr Hawker.
Schools need to build on existing work. Schools already involved in Sure Start are familiar with integrated services and find it easier to adapt.
Once people understand each other's professional roles, they work better together. It also means that teachers understand more about children's out-of-school lives. "Inclusion goes hand-in-hand with achievement," Mr Hawker says.
Integrated services are where the standards agenda and the care agenda meet. If children with difficulties get the help they need, they do better in school.
The switch to children's services will affect every child, says Mr Hawker.
"You never know when they might need a service," he says. "Most children may need a helping hand at some point along the way. Where a school gets inclusion right, that school is likely to have the right kind of approach to all children."
He adds: "The test of an education system is how it treats the most disadvantaged. The test of a healthy school is whether it seriously looks at every child's needs."