The plie, or bending of the knees into a squat-like position, is an instant rear lifter. Start with your feet in first position, heels together, toes pointed outward. Suck in your stomach, push your shoulders down and rotate your hips under so your butt is tucked in as much as possible. Slowly bend your knees, keeping your heels on the ground as long as possible until you have to lift them as you lower farther. Make sure your knees are directly over your toes. Slowly rise coming back to your starting position. To do a demi-plie, do not lift your heels; instead bend your knees just until you're about to lift them and then straighten again. Do these 30 times each.
Two of the most basic ballet movements, the releve and the eleve, are some of the best calf toners around. Start with your feet in first position. Hold your torso tall, stomach sucked in and butt tucked under. Slowly rise up onto your toes, keeping your heels turned inward and your hips out. Hold for a moment, then slowly lower back down to first position in a controlled manner. Repeat 30 times. Then add a demi plie (bend your knees but keep your heels on the ground) before each rise so you spring up onto your feet instead of slowly rising. Repeat 30 times as well.
Start with your arms out in a circle in front of you. Keep them away from your body, elbows rounded and lifted at all times. Make sure your wrists are level with the rest of your arm and bring your middle finger and thumb in so they almost touch. Push your shoulders down and hold this for one minute. Then raise your arms above your head, maintaining the same position. Hold this again for one minute. Open your arms up to the side, maintaining the same rounded and lifted elbow position and hold for one minute. Repeat two to three times a day.
Do lots and lots of crunches. Honestly, a variety of crunches combined with all of the other ballet movements listed is your best bet. Abs develop as you control the rest of your body and force it to move slowly in a methodical manner.
Bourrees are one of the best workouts for the thighs. Stand on your toes and cross one foot in front of the other so your ankles cross. Squeeze your thighs together and hold your upper body strong. Beat your feet into the floor as you pick up one foot followed by the other; right, left, right, left and so on. Keep your feet close together and squeeze in as you move across the floor. Never allow more than 2 inches distance between your feet as you step--it is a lot of quick steps, not long-reaching, slow steps. Switch and start with the other foot in front so you travel across the floor in the opposite direction. Do this for five minutes each day.