The story that Lawrence writes bears the entire existentialist anguish of the 20th century. The boy needs a parallel and imaginary universe, with the horse as its centerpiece, on which to base his existence, mainly because of an attempt to avoid and evade his own existence. This is where his imagination meets his remarkable gift for choosing horses at the race track.
On the other hand, in Greenes story, the existentialist anguish that the teenagers might be themselves starting to experiment, does not reflect a tragic perspective, but more of a phase of life that everybody has to pass through (which is why Old Miserys remark that he was a boy once as well is important). The prank, despite being conceived with a master plan, is still just a teenager prank.
It is interesting to note, and this is something unique to Greenes story, the way in which the relationships within the group develop. Although not intentional, Blackies authority over the group is questioned by Ts presence. T brings something new to the group: imagination (a common theme between the two stories), which means that he promotes a challenging way of thinking which will diversify the activities of the group as well, something very important at an age where you tend to get bored quite fast.
On the other hand, just as in any group, the moment that Ts newly discovered authority is questioned, his whole persona becomes doubtful, whether he would be able to continue to survive in the group or not. Blackies attitude and his own regained leadership helps Trevor stay on track with his project in the group, but it is interesting to note how the adolescent cruelty might have immediately exploded at that point within the group.
None of these group relations can be studies or noticed in Lawrences story, where the characters generally just have their own individual relations and do not build on these to interconnect at a group level. The boy interacts with his uncle, with his mother or with Bassett, but these are just individual, isolated interactions rather than something at a higher level.
Despite their similitude of the approach towards existentialism and the many questions that an individual is likely to pose during his lifetime, the atmosphere in the two stories is very different from one another. The teenager atmosphere in the first story gives way to the gloomy and oppressing one in Lawrences story..