I have a memory of a movie I saw around 8 years ago on tv. It focused on a boy who went out to the country, possibly in england, and was about him using his imagination a lot, with most of the story having to do with what he is imagining I think. I remember there was a junkyard or lot of land he was in for most of it, and I remember the ending was him riding away looking out the win down of a car. I think the movie was a bit older than the date I saw it, maybe from the early 2000s
Could it be “Carrie’s War?” The lead character is a girl, who along with her younger brother, are sent to foster in the English countryside during WWII. The last scene, before the short “modern times” ending, is close to what you describe.
http://www.imdb.com/title/tt0364254/?ref_=nm_flmg_act_31
I don’t think that’s it, but its a very good guess.
Bridge to Terabithia (2007) ?
http://www.imdb.com/title/tt0398808/?ref_=nv_sr_1