Sounds like you have a pretty heated summer! I've been flying in a C172 for a few months now here at CYKZ. It is a great thrill flying in a C172 because it is not too small (for example, the C150) but you still have that feeling of being in a prop plane. Assumingly, you will sit in the left-hand seat, so you will get to see all the controls which is pretty neat. I find that during training, it's a lot of fun taxiing and even doing the walk around. You can expect a rather quick t/o, lasting maybe even 10-15 seconds. Climb out is pretty quick and you will be so distracted by all the beautiful scenery and views you are seeing that you wont even care about turbulence or anything of that nature. Cruise is when you'll notice your turbulence, that is if there is any. I'll tell you right now Dan that you can expect turbulence on your flight. I'll confess, I too had a little fear of flying, although it was mostly turbulence oriented. What I do is say to myself that there will be turbulence each flight. There usually is. If you go into your flight during the summer saying "I expect that his flight will have no turbulence whatsoever. I mean, look outside; it's absolutely beautiful.", you will most certaintly notice the turbulence. It's like when going into an exam, and you are not sure what will be on it. You can obviously expect that the topic you spent the most time on in class will make up a large portion of the exam. With that being said, the turbulence in a C172 is not worse than that of a B744. You will notice a bit more un-intended movement (ie wind ) in a C172 than a B744, however, because of the weight difference.
So, all I can suggest to you is to expect turbulence for your flight. I do, and it works! For descent, you can expect it to be quite quick and a bit less relaxed than cruise, due to reviewing charts, maps, radio calls, etc. Landing is the best part, for me. It makes you feel powerful, to say the least!
For your flight, the PIC will most likely let you take control during cruise, perhaps even t/o. The worst thing you can do is grip very tensely on the yoke. Instead, gently rest one of your hands on one side of the yoke, allowing the plane to do most of the flying itself. Overall, you will have a very good time this summer in the C172 and I wish you all the best.
By the way, if you have any further questions, you can send me a message.
"If it aint boeing, it aint going!", "Friends are like condoms...they protect you when things get hard!"