These are the two way that my joints would be able to aggregate to create a structure. By angling the original joint, and joining it with two other joints and the other way would be to join the original joints in a 90 degree manner.
This structure is transformable, either through adding more joints to it or just changing the positions of the individual joints. This makes this structure more appealing because it becomes an interactive structure that can be designed and then redesigned. By making the structure transformable, kids wouldn't get bored of playing on it and continue to enjoy the park, because there is something different to play with from time to time.