Game based around a tree.
One person would be elected the 'puller' and the rest of us would grab hold of the tree trunk for dear lives. The puller would attempt to remove pupils one by one from holding onto the tree by sheer force and if you were removed you then became a second puller and were then employed in removing others from the tree. The winner was the last one to be left clinging onto the tree.
This game, however, died a rapid death after some of the older boys said we all looked like we were trying to shag the tree. It did too.