Flaps are pretty misunderstood. Generally on full scale they're used to increase the sink rate and lower the landing speed. Current practice on most full size is that they also significantly increase the wing area when deployed.
On our controline models I pondered for many years why on earth I wanted a movable surface on the wing that increases the moment opposite of the horizontal tail, which would reduce the total pitching moment. I also knew that a Flite Streak, Shoestring or Sneeker would turn pretty danged tight without a flap.
Years of study and application later I kindof sortof think I understand it now.
Like all things aeronautical, you have to remember that what you do in the front of the airplane affects the back of it, i.e., you alter the flow field around the aircraft, not just the wing. That's the key thing to remember.
Besides shifting the lift vs AoA curve to the left flaps do two other major things at the airplane level:
i) they change the wing's angle of attack since the airfoil's centerline has been shifted.
ii) and this may be the most important on a CL ship...they alter the flow field around the horizontal tail. They change the trim angle of the horizontal stab.
Number ii above explains why, many many years ago while flying a Top Flight P63 with an ENYA .35 ( with the square black plastic venturi insert! ) I had the elevator horn break and was still able to maintain some control with the flaps only. In airfoil only theory, the controls should have reversed. In practice, they did not.
Later in life, on my full-size sailplane I did some flight testing, since they flaps went +90/-10 degrees. I "locked" the stick with my hand and used the flaps to see if I could maintain pitch control with no elevator input and lo and behold... flaps go up, nose goes down. Flaps go down, nose goes up.
Also, a comment was made that flaps can only move so much before a stall. Gross over-simplification. It's dependent upon the flap chord. Case in point my sailplane again: with 90 degrees of flap the wing was not anywhere near stalled.
I will admit however, that in a aircraft with no power and 90 degrees of flap deployed, the view out of the bubble canopy is...impressive! You get a very good view of your intended landing area.
But back to flaps on a CL plane - and I have no numbers to back this up - here's what I think happens:
Flaps go down, nose down pitching moment of the wing is INCREASED but the change in AoA plus the increase in downwash on the tail causes a net overall increase in the nose up pitching moment. In other words, the total nose-up pitching moment of the aircraft is increased even though the wing's contribution is against it.
YMMV.
And you know, now that I think about it, increasing the wing's AoA will INCREASE the nose-down pitching moment, since the CG is ahead of the center of pressure, so it must have more to do with the downwash.
Crap, we already know that. When an airplane stalls the nose drops. Your flight instructor told you that's because the wing isn't making lift anymore. But that can't be, because the lift is behind the CG, so the nose would go up if the lift vector went to zero. We also know from wind tunnel data that a stalled wing is in fact, creating tremendous lift. The reason the nose drops abruptly is due to the change in moment and flow field! Whoohoo!