A third of teachers think schools are failing to prepare pupils for life in the globalised 21st century, a survey has found.
The survey of 848 teachers, commissioned by education charity DEA, found that many lacked the confidence or knowledge to discuss issues that will affect future generations.
For example, almost half did not feel able to teach about the impact of emerging economies, such as China and India, on daily life in Britain.
Hetan Shah, chief executive of DEA, said: "The realities of a globalised world are all too clear, but our schools are not keeping up.
"This has serious consequences for young people, who will leave school without an understanding of the issues that shape their world."
John Dunford, general secretary of the Association of School and College Leaders, agrees. "Syllabuses only change slowly, but the world is changing rather fast. We must change to reflect the new world order."
The findings support research conducted by DEA last year, which revealed that a fifth of pupils were likely to leave school without an adequate grasp of major world events.
The charity compiled a series of recommendations and suggested ways in which the Government could ensure that teachers were sufficiently prepared to debate world issues.
In a report outlining the recommendations, Mr Shah said: "We must ensure that young people are prepared for their global futures, and can respond to the world around them with optimism and positive action rather than fear and powerlessness. The key to this will be to provide teachers and heads with the support they need."
The charity called for teacher training courses to cover topics such as sustainable development and community cohesion. Would-be teachers should be trained to deliver philosophy for children, and to encourage inquiry and discussion, it said.
DEA believes global awareness, rather than being confined to citizenship lessons, should be incorporated into all subjects. For example, language learning could highlight different cultures.
The DEA report argued that the new masters qualification in teaching and learning should include specific modules on sustainability and diversity.
It also called for headteachers to support open discussion of controversial issues: "All leadership courses should include the explicit consideration of embedding global learning in the curriculum and wider school ethos, to ensure outward-looking schools."
The DEA recommendations will be launched next week, in advance of London's G20 summit of rich and emerging nations next month. The charity wants to persuade ministers that their development, sustainability and community-cohesion goals will only be met through school-based education.
The recommendations have been backed by all the major teaching unions.
John Bangs, head of education for the NUT, said: "There's still a lack of connect (sic) between the general pessimism of young people about climate change and giving them the tools to tackle it. Teach about it; teach practical ways to make a difference.
"But there needs to be genuine discussion and debate within the profession. If it's just another insert into teacher training, it'll be referenced once and that'll be it. And that's not enough."