Pupils could be challenged to visualise how the different cubes
could be constructed from the net.
Perhaps working in pairs, pupils could try to convince each other
why (and how) certain cubes can be made, and why certain cubes
cannot be made.
Copies of the printed sheets, scissors and sticky tape could be
made available at a later stage to allow pupils to cut up the net
and make the various cubes.
The second part of the problem could be tackled in a similar
way.