A study reveals that, for some, the prospect of schools offering longer hours and extra-curricular activities meant a sense of disruption and "constant worry".
"While they find the potential of their extended schools exciting, they are struggling to adapt to it," says the report by the left-leaning think tank, Demos. One head said: "In the past, being a head was like playing football; you knew your position and where you were on the pitch.
"Today it's more like orienteering; you don't know either of these things so you have to rely on your wits and on other people."
The study found heads were operating in a "leadership vacuum". The Government was urging schools to innovate, but schools were fearful of taking the initiative.
The study, commissioned by the National College for School Leadership and based on evidence from seminars with nearly 400 school leaders, also found heads of extended schools were having to play a more political role.
It gives the example of a head who worked with Jobcentre Plus to help unemployed parents of Year 10 and 11 children find work, in the hope that this would benefit pupils' learning.
"This is an example in which a school leader's decisions impact on the distribution of the key resource of employment across an entire community,"
"Such a decision is inescapably political, drawing leaders into new kinds of relationships with local people."
The report recommends more support for heads and for the college to research the connection between school leadership and local politics.
Maggie Farrar, the college's assistant director of programmes, said it was launching a new extended school leadership programme in the spring.
Taking the wide view: The new leadership of extended school, by John Craig, Demos www.demos.co.uk
Get your head around wraparound care...
Children's agenda, 33