Have ever seen dancers hold their legs right next to their heads, do really high kicks, and all sorts of splits and straddles? Ballet dancers stretch every day for at least 1 hour!
Stretching is great exercise that is really important to do it before and after dancing. Although it is not very fun, and requires a lot of mental power in order to endure some discomfort, stretching has a lot of great qualities: It helps you maintain flexibility, reduce the chance of injury, it helps calm the mind, and it can even eliminate some body pains (lower back, hips shoulder pains). If you want to be able to dance as you grow older, you need to stretch!
Sessions can be done from 5 minutes to 1 hour, usually the longer you hold the stretch the more benefit you get out of it. As a dancer stretching allows you to further your range of motion, which means that you will be able to the splits and kick higher. As a part of your warm-up, it allows your muscles to loosen up and reduce the chance of injury. Stretching requires you to focus on your breathing and to maintain concentration therefore it can be a good aid in calming the mind.