Ministers have announced more than pound;190 million to help local authorities introduce the Every Child Matters strategy, which aims to join up public services so they share information about children.
Margaret Hodge, children's minister, expects that most changes will be funded through existing budgets in schools and other institutions.
However, in a report this week, MPs on the Commons education select committee dismissed her view as unrealistic. The cost of retraining teachers and other staff could prove particularly expensive, it said.
"It is not clear that services will be able to meet the costs that they will incur," the committee said. It warned that the Government's plans to make schools more independent - by, for example, making it easier to gain foundation status - would also undermine the strategy.
"We are deeply concerned that some schools may choose, for one reason or another, not to participate. This has the potential to fundamentally undermine the aims of Every Child Matters.
"It is unlikely that the current incentives and penalties in the system will be adequate to make reluctant schools co-operate."
The committee also noted that there was too little evidence to support the plans for a network of computerised databases.
Mrs Hodge told The TES that she felt sufficient additional money was being provided, although smart use of existing funding would be equally important.
"There may be some schools that don't understand that inclusion and raising standards are two sides of the same coin," she said.
"But there are going to be lots of levers in place to encourage those school, and financial incentives."
Every Child Matters is at www.parliament.uk