After realising that tour will end on Saturday after breakfast and not Sunday as I thought and adding on an extra day so I can attend church at All Saints Cairo i did a bit of research today of things I can do to fill in the Saturday.
Yes I am going to be a bit braver than last time and venture out from the hotel. 
Have discovered that I will have more than enough to fill in a day just staying on Gezira Island where the Cairo Marriott is situated.
Is a bakery attached to the Marriott so have decided for starters that a picnic lunch would be a good idea as they do take aways.
Are some nice formal gardens on the south of the island which cost all of 2EP to enter, this would work out in NZ 40 cents!
These gardens include the Gezira Gardens, the Andalusia Formal gardens, the Aquarium Grotto Garden and the Gezira Sporting Club which has walking paths around it.

Link to infomation about some of these gardens
  http://www.touregypt.net/featurestories/aquarium.htm
 
Cairo tower is also situated on the island too, it does cost 70EP to enter but again that works out at about 14 NZ dollars.
Cairo tower is 187m tall and was constructed between 1956 and 1961. Interesting it has a revolving restaurant at the top, did not know this until today.
It was apparently built with $100,000  that was given to Gamel Nasser by the Government of United States as a personal gift with the intent of gaining his favour. Nasser decided to rebuke the US government publicly by transferring the total sum to the Egyptian Government for the building of the tower. 
 

  By Ahmedsantos (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons

These are a few of the sites I can visit, I'm sure I could find a lot more too if I wanted.