Leading characters in fiction usually have a long way to go.

Sometimes their voyages are explicit, as in Anne Holm’s 1963 novel I Am David, describing the adventures of a 12-year-old boy escaping the communist concentration camp in which he has grown up and journeying across Europe to Denmark in the hope of reuniting with his mother.

The book is a popular choice at key stage 3. UK sales over the past three years have topped 60,000. And now it has been filmed with Jim Caveizel (The Passion of the Christ) as Johannes and Joan Plowright as artist Sophie - the allies David (Ben Tibber) acquires on his lonely path to freedom. The film provides a chance to explore the kind of transformation, not always kind, that a book can undergo in the process of becoming a movie. It is also a means of raising the plight of today’s young refugees, at a time when under-18s account for about half of the world’s 50 million people displaced by wars or civil unrest.

Teachers familiar with the book will wonder how a film maker would deal with some of the novel’s challenges, particularly the highly introspective nature of a narrative tracing David’s slow acquisition of understanding and trust in a world that seems, at first, utterly alien and hostile. How, too, will they approach David’s language development as he learns to match words he knows to objects he has never seen, and what will they do with the idiosyncratic relationship he develops with God as celebrated in the 23rd Psalm?

The simple answer is that director Paul Feig chooses largely to ignore these elements in the twin cause of brevity and the literalness required of a mainstream film. Not that these are bad qualities - it is telling how the book has had to be tidied up for the screen. Gone, for instance, are the most unlikely of the novel’s coincidences and most of the last two chapters. There is no blizzard on the ItalianSwiss frontier, no second imprisonment and enslavement at the hands of cruel farmers and no boy-and-his-dog action. It would make an interesting activity to get pupils to consider why the film might have had to drop these sequences and whether the story is weaker for their removal.

In the end, the film largely succeeds or fails on the strength of Ben Tibber’s performance as David. Getting pupils to consider the challenges the role contains for an actor is a way of helping them engage with his representation in the novel. For one thing, there’s the difficulty of capturing his remarkable appearance - the eyes that adults are forever finding uncanny. Then there are his muted emotions - a product of prison-camp life, which only start to develop following his rescue of Maria, when he finds he has the capacity to smile. Feig preserves this moment. Overall, Tibber’s David is an altogether sweeter creature than the highly judgmental and unforgiving David of the novel.

What the film really does justice to is the powerful sensual shock for David when he finally lands on the Italian coast and encounters beauty for the first time. It is a compelling cinematic moment when he awakes and experiences a world of vibrant colour after a life spent amid the greys of the camp and its ashen inmates.

In keeping with the novel, the film is pretty spare when it comes to depictions of camp-life. That said, there is sufficient detail to ask the same questions in class that Spielberg faced with Schindler’s List concerning the “rightness” of recreating essentially unrecreatable human suffering. It would also be interesting to get students to study the way the role of Johannes is altered so as to condense his loyalty to David into a single brutal moment, slowly revealed in flashback via David’s dreams.

In the end, the film’s greatest potential in schools will be in helping deepen pupils’ understanding of the forces that drive people to flee across international borders. It throws into perspective the enormous challenges facing today’s young unaccompanied refugees, entering an often hostile Europe without David’s linguistic abilities, luck and opportunity of returning home.

I Am David is published by Egmont Children’s Books pound;4.99. Paul Feig’s film I Am David (PG) is released on November 5. It is due to be supported by an extensive set of free on-line study notes www.filmeducation.org

Refugee Council www.refugeecouncil.org.uknewsmythsmyth001.htm

UNHCR teaching resources www.unhcr.org.ukinforesourcesteachtools.html