Students who have an Android phone can download a free graphing calculator app to use on their phone! It is called WABBITEMU and is only available on Google Play Store. When you install the app, let it create your ROM file and download the OS. When it asks you what version you want to emulate, select the TI-84+CSE. It is the best one out there!
If you do not have an Android phone, you can still install the program on your Computer by searching the web for Wabbitemu and following the prompts. Or you can visit my document manager and there is a link to a different version that is a little different than what we use in class.