Former Education Secretary Nicky Morgan announced last July that Barnardo's would help Norfolk County Council run its looked-after children's services to help it improve, but the plans failed to attract backing from the social care innovation fund, which turned down the grant application.
Now the pair have said they will start a separate joint project this month designed to reduce the number of children in care.
The New Directions service will give intensive support to families at risk of coming into care, and help return children home from care, whenever it is "safe and in their best interests".
The service will be managed by Barnardo's, with Norfolk County Council staff.
Penny Carpenter, chair of the children's services committee at Norfolk County Council, said: "We know that most children do better when they are looked after within their families.
"However, there are circumstances where we have to recommend care orders to the courts because staying at home is not safe.
"We have already developed services to support families in crisis, including a short breaks and outreach service, but we need to increase the pace of this work further and are confident that Barnardo's input and expertise can provide us with new ways of helping these families.
"It is also important to get children home and out of our care, where we can. This new service will help strengthen and support families to make that possible."
The council is currently trying to turn around standards within children's services after provision was rated "inadequate" by Ofsted for the second time in two years in October 2015.
Monitoring reports conducted since then by Ofsted have found signs of improvement.
Director for Barnardo's East region, Steve Oversby, said: "We're very much looking forward to working in partnership with Norfolk County Council and delivering quality services to children and young people across the county.
"As the UK's leading children's charity, we're proud of our strong track record when it comes to helping children and young people to achieve the best in life. We are committed to working closely with the council to ensure that Norfolk's children and young people benefit from our experience and expertise."