I know I have already written once about flexibility, but this is specifically the splitz. First off, many people say they are struggling getting all the way down. You need to stretch your splitz everyday if you wish to get them. I recommend fifteen minutes on each leg outside of class. Make sure you are properly warmed up as well. Some people may have a dominant leg also. For me it is my right leg, for some it is the left. If you don't feel like stretching each leg fifteen minutes, stretch your dominant leg five. Generally because it will be easier and you will be able to get down further. Then stretch you less dominant leg for fifteen minutes. If you are still in school, you can stretch your splitz while you are doing homework, (Only if you are close to the ground though.) Splitz will help with the battements to the front and back, and they will help you with your airabesque, if you need to get it up to 90º. If you would like to have a more deep explanation of how to get your splitz check out this website: http://drillobsession.com/2006/09/03/flexibility-to-the-maxstretch-your-splits-in-3-weeks/ and do some more research on your own. This website is also posted on my links page. Any questions, ask them right here on the comments, or email me at [email protected], as well as contact me on my google + page, Ballerina Blog. 

Casting, it is something all of us dancers fear. Why is it so scary, it is because it determines what role you will be playing in a show, and it could depend on your future. First of all, remember no matter what you get cast put your best foot forward, and make sure all that you care about is dancing. It doesn't matter if you are in four scenes or ten, just be confident in what you are doing and believe in yourself. 
Got cast the lead? That is awesome, you are in a principal spot. Don't go around bragging about it, tell a few people once and you are done. Don't lie to someone if they ask you about it, just say oh yeah I got the lead.
Got cast as an understudy for an apprentice role? It is alright, take a deep breath and calm down. Show whoever cast you as that your stuff and be the best understudy possible. Always do the steps full out, and be confident. 
No matter what you are cast be confident and happy with it, you are sure to shine on stage. 

Flexibility, it shows the way dancers can defy gravity. Lifting their legs, high, seemingly. Flexibility, it is a beautiful thing. So flexibility may seem very necessary, but it isn't needed to the extreme.
Being flexible, just means you can sit in the splits right? Well, that is what it used to be, now it is one foot over splits is flexible, in each position. If you can kick your leg up above 100º, that is probably okay. Don't push the stretching, try your best and that is all that counts.