Some C&C Please. I am still very new to my DSLR but I like to see how I can improve.
To improve, start with the basics:
Digital Photography Tips For Beginners
How To Improve Your Photography - Five Easy Tricks
Get to know your camera really well. Read the manual and know what each and every button and knob is for.
Take control of your shots. Get off the green box AUTO mode (or any of the other Basic Zone modes) and get into one of the Creative Zone modes (P, Av, Tv, M).
#1 - It's a nice shot...subjects aren't centered but you could have gotten closer to have them fill more of the vertical space in the frame. Right now it looks like the main subject of this picture is the trees and snow and not the girl with the dog.
It's nice to see her looking into the frame. Exposure is good.
#2 - Shutter speed was too slow (blurry dog). Sun on the face of the girl is straight on and making her face look flat. Better to have light come in from the side a bit to help give structure and volume to the head and face. Or have subject go into the shadows.
Subject is centered in the shot. This makes them look static and boring. Compose the shot with the subject off-center. You might want to try shooting in the portrait orientation too just to see what it does for the image.
Background is distracting. Using a bigger aperture (small f/stop) will give you a reduced depth of field (DOF) and keep the subject in focus but put the background out of focus...this helps to isolate the subject.
#3 - Looks cold.
All the pictures look a little soft. Could use a little more sharpening.