Besides Jim Anderson who is also a boy, there were three other boys namely:
Mule
Mongoose and
Milo
Explanation:
The other boys were introduced in chapter one when Jim meets them. They had considered him somewhat a laughing seeing that he was not bare-footed as they were. He had his feet "covered" with shoes.
Later on in that chapter, he tries to join them but they would not agree easily. They agree on one condition that he would perform an impossible task. So in order to become part of their "club", they ask him to catch a hawk alive.
