spastic water temp?

my car has been having overheating problems for the last 6 months. lately its randomly gotten better but it still does some weird crap. the gauge will stay at one spot normally cold then when driving it gets up to the half way mark on the temp gauge then goes back down and it keeps doing that for as long as i drive. sometimes the temp gets really up there then slowly goes back down.. what causes the rapid tempt changes? the thermostat is basically new

I would suspect the cooling fan motor is going bad. When driving if it goes up turn on the air conditioning this turns another fan on. If the temperature quickly drops its a good sign the other fan motor is going bad. I've tapped them with a hammer when they won't turn on if this works get a new motor.
I have gotten then from pull apart junk yard they are cheap.

the thing is though i can hear the fans when i turn off my car.. they make that cool slow whine. could it be that the radiator is clogged or something?

The radiator can definately be plugged. You can take it to a radiator shop to be cleaned and rodded. With the radiator cap off watch for flow through the radiator. The top and bottom hoses should both be hot.
I thought said it was something which happened occasionally.

yeah i think its just clogged.. heres another weird thing my car does. whenever i turn left or make a u turn it cools it down when the temp doesnt want to go down by itself... is that a normal corsica thing like bucking and bad heater cores?

I've drove a few citations company cars and this never happened. I used to inspect the company cars and have found plugged radiators.