http://www.becominghuman.org/ might be able to give you some help - watch the documantary and get some ideas. Other useful resources at
http://www.biozone.co.uk/HUMAN_EVOLUTION.html which should answer query and give you help.
Humakind evolved from a common ape ancestor that led to bonobos, gorrillas, chimps & orang utangs. 4 million years later we differ by less than 2% in genes from bonobos but here are arguments we are not the most intelligent - been out on a Friday night lately?
Maybe bring in the Darwin Awards - funniest examples of natural selection you'll ever come across -
http://darwinawards.com/
Human evolution is without doubt linked to the development of farming and animal husbandry - lots of info around about the spread of humans into the Indus Valley region that allowed through chance the development of cultivation in temperate zones.That meant growing crops and utilising the animals for food, so releasing time for society to advance.
So for activity - maybe link in farming - and then what to do in spare time that offers- art, culture, language, religion, etc.?
Hope this helps.