Windows editions follow a naming convention which may not be the clearest and, to make things worse, change with Windows versions and cover both technical and non-technical differences (meaning that two different editions may actually be the same with just a different EULA).
Here is a short post on main Windows editions with a focus on the version you may prefer for your lab.
Windows client editions
Windows Home or Core edition is the low-budget, consumer grade version of Windows. It is enough for home uses, but is missing features necessary for corporate environments such as the ability to join an Active Directory domain.
Windows Professional or Business edition adds more functionalities, such as the ability to join an Active Directory domain and disk encryption (limited to the Enterprise edition and above until Windows 7 included).
Windows Enterprise, Education and Ultimate editions are the most complete editions. There is little …