Police said the Year 9 student had been moved to a more specialist unit at Southampton Hospital for his injuries and that he is now stable.
The collision, which took place around 16:30 on Thursday 25 May, happened on the junction between Rue du Hucquet and Rue de la Vignette in St. Martin.
The teenager, who was wearing sports clothing at the time, was taken to the General Hospital and later transferred to Southampton.
An appeal has been put out by police for any islanders who have CCTV or dashcam footage of the teenager or the van in the surrounding areas, or anyone who witnessed the collision.
Islanders should contact 612612, go to Crimestoppers anonymously on 0800 555 111 or use their anonymous online form.
