Essays / Organisational Behaviour Essay (how to approach this essay?) [2]

Hi,
I have an essay due on 11/01/2011 for Organisational Behaviour. It is 50% of my mark so it is very important. the essay question is about:

Recent events in the banking sector have brought the issue of bonus payments into the spotlight. With reference to appropriate motivation theories, critically evaluate the statement that "money motivates".

I am not asking for someone to do my essay for me but just pointers on how you would approach it.

Currently i have thought of using the Herzberg motivation theory where he suggests that money is more of a hygiene than a mativator.

Could someone please give me a pointer on how to approach this essay (it is my first university essay) i mean like should i approch it by doing

Intro

Theory 1

Theory 2

Theory 3

Conclusion

Also what does "Critically Evaluate" actually mean??

Thanks