Speed crunches - on back, legs up, and cross your feet. And crunch fast! Bicycles - You're gonna lay on your back and shoot your legs back and forth like pistons, bringing your opposite elbow to the knee as it comes back. You should twist your torso, and lift your shoulder off the ground. (i.e. Right elbow to left knee) Boxer crunches - Lay on your back with feet down, knees bent. Crunch up, and twist your torso left and right so that your opposite elbow goes to the opposite knee. Bring your right elbow to left knee, left elbow to right knee. The key is to twist your torso FAST. V-ups - Sit on your but with your hands behind your back on the floor. Your feet should be crossed and off the ground. Crunch your knees up to your chest, like a V. Hip tilts - Lay on your back, with your legs in the air. Arms flat on the gound at your side. Roll your hips back and lift up in the air. The goal here is to keep your feet high. This is not a speed exercise like the previous ones. Snap touches - Very similar to hip tilts. Lay flat with your legs out straight on the ground, and your arms flat laying over your head. Crunch like a V, lift your shoulders off the ground, and without bending your knees, touch your toes with your hands. Also not a speed exercise. "Do it right, not fast" 6 inches cycle - Lay flat with your feet 6 inches above the ground. Some "fun" variations of this are to lift your legs to 12 or 18 inches, lift one leg up at 12 and the other at 16, alternating lifting your legs up and down, etc. They're kind of hard for me to explain throught text, but if you need more aid I can look for videos of them on youtube.