It's about time to start school, college, university, you name it. It always comes in handy to have a nice and powerful device to do mathematical calculus when a class requires it. I am a huge sucker for those big and bulky calculators. I am a nerd at heart and soul.
There are various options in the market of these great calculators. For example, the Texas Instruments brand have a really nice and great quality calculators. This model, the TI-84 Plus Silver Edition is the one that most of my fellow class students were using at high-school and was a rock. And you can change the cases of this calculator any time you want to the colour you desire.
The next calculator was the one that all of my friends used. It is a Casio CFX-9850GC Plus in colours. It was, and still is, my baby. It is great to draw graphs, do derivatives, equations and every other mathematical problem your teachers present you. This model was recommended to us by our science teacher. He swore on these calculators and he was so right. I use it for everything from a simple add up of 60+96 or a very long 2 variable equation.
Another calculator, also from Casio, is a more recent model of my dearly beloved GC plus. It is the FX-9860GII. It has all the features of the later calculator but also has a USB cable in which you can download every data you have, both in your computer and the calculator, to have it everywhere.
So with any of these calculators you could be prepared to rock those maths problems and get good grades hopefully. Before you buy them, be sure that they meet the requirements for the classes and what the teachers recommend. There is also a great variety of non-graphic calculators, which are much simpler to use.
I hope you are having a great end of vacations and enjoy your last bits of freedom!