Download Skype and install it on your computer. (or, if you have already installed Skype on your computer, continue to step 2)
Find skype.exe file where it was installed. (Normally found at C:\Program Files\Skype\Phone\skype.exe)
On your USB drive create a folder and name it "Skype" and copy skype.exe into this folder
Create another folder in this newly made Skype folder on the USB drive and name it "Data"
Create a new file in Notepad and add the following text: skype.exe /datapath:"Data" /removable
exit
Save the file as "Skype.bat"
Make sure file is located in the Skype folder you created in step 3.
To launch skype, double-click on the batch file located in the Skype folder.
Benifits:
- No installation on local machines - Will run on restricted accounts
- Students can only use Skype if they have the flash drive
- Skype could be checked out with webcams
Technology 
