Given the nets of 4 cubes with the faces coloured in 4 colours, build a tower so that on each vertical wall no colour is repeated, that is all 4 colours appear.
Label the joints and legs of these graph theory caterpillars so that the vertex sums are all equal.
Label this plum tree graph to make it totally magic!
Use the Thesaurus if you don't know how to find the subsets of a given set.
In counting the tours remember that you can start from any vertex. From the start there are 3 possible ways to go and at the next vertex two ways to go.
Can you label the vertices of a cube with the subsets of the given set so that an edge connects two vertices if it is possible to move from one subset to another in the sequence?