Sit ups vs crunches?!

Sit ups vs crunches?

I use to do sit-ups now I do crunches but it dosent feel like it is working my abs. I just go up barley enough so that my shoulder blades are off the ground. right?

yes, this is right. Crunches only work the top part of the abs. They aren't as hard on the lower back as a full sit up. However, there are exercises to work the lower abs..which means the navel area and below. Lie down on the mat, place your hands under your butt (if necessary to give support to your back) and lift your bent legs up towards your chest. Kind of hard to describe with words, but these are reverse sit ups that work the lower part of the abdomen.