The Johnny Maxwell trilogy - Terry Pratchett

Terry Pratchett's Johnny Maxwell trilogy are three of the few non-Discworld books he has written. Johnny Maxwell is 12 in the first book (Only You Can Save Mankind), and a teenager in the second (Johnny and the Dead) and third (Johnny and the Bomb) books. He has a difficult home life as his parents split up over the course of the three books, and he and his mother move in with his grandfather. This may be why he starts seeing things nobody else can see; on the other hand, it's possible he sees them because they're actually there, and Johnny lacks the filters that stop most people noticing how amazing the world is. (This is a favourite theme of Pratchett's.)

Apart from his tendency to see things no one else can see, Johnny is almost unnaturally normal. His friend Kirsty often gets exasperated by his tendency to simply accept the strange things that happen to him, rather than doing something about it, but Kirsty is over-organised, scarily feminist, and very intelligent. Johnny has a strong sense of fair play, which leads him to fight for what is right, even when he has no idea what's going on. He's clearly very sensitive to history, as both Johnny and the Dead and Johnny and the Bomb demonstrate; in the former book Johnny can see the dead soldiers of the Pals Regiment that turns up to collect their newly deceased comrade in arms, Tommy Atkins, and he realises that they are heading back to France where all but Tommy died in the First World War. In the latter book Johnny has been working on a school history project about the experiences of his town (Blackbury) in the Second World War, and when he becomes the temporary owner of a shopping trolley full of black bags full of Time, he and his friends travel back in time to 1941 and the day on which 19 people were killed in Paradise Street after the German bombers, lost in the thunderstorm, drop their bombs on Blackbury instead of the railway yard over in nearby Slate.

In Only You Can Save Mankind, Johnny's innate sympathy towards others leads him to enter the eponymous computer game via his dreams in order to accept the surrender of the alien race which players of the Only You Can Save Mankind (TM) game have to overcome, and help them find the way back to their distant home in the stars.