coming up with stuff for a specific question
Cool cool, so:
With regard to purpose of punishment - You should consider some specific case studies to illustrate your points. Consider the punishments and what purpose they appear to take - Is it strict or lenient? Is it targeted at deterring the offender? Protecting the victim? The approach taken for punishment will ultimately reflect the values of society through how harshly a crime is punished.
R v Loveridge and
R v Singh could be two good cases to examine
For Age of Criminal Responsibility/Children - Similar premise. Does society value a lenient/welfare approach to juvenile justice? OR does it focus instead on punishment/detterence/retribution? Again, the approach taken will reflect societal values. The Three Tier System is a must mention here (cases are a little tough to come by in this area, but if you can find them, they would work well just as above!)
Just a bit of a brainstorm, hope it helps