PADI announced the computer-based course in 2009, effective Aug 2009, and noted the previous training materials were now officially outdated. They provided new materials.
In the first quarter of 2011, instructors were reminded that the change to computer training had to be done, that the then-current EANx manual no longer even discussed tables. Tables were still available, and could still be taught. That is still the guidance: the standard training materials are for computers, but the tables are still available and must be supplemented with additional training materials. The 1Q2014 PADI Training Bulletin (required reading for PADI instructors) says, "If you choose to teach the PADI Enriched Air Diver course using dive tables rather than dive computers, a table set is available (metric or imperial) that includes the Equivalent Air Depth Table, Oxygen Exposure Table, EANx32 RDP, EANx36 RDP and an illustrated study guide that shows the student diver how to use them."
I know a number of instructors teach the computer course, but then supplement it with the additional material. Since the students will almost certainly be diving with a computer, this serves them well.
It sounds like your 2012 class was using older manuals that still had the math in them.