Orwell took the message of education full circle in Animal Farm illustrating its importance, usefulness and its misuse. Notice that one of the first thing that the pigs do is to educate themselves and sets to trying to educate the other animals of the farm. At this point, the pigs have realized the value of education and are trying to educate the farm's inhabitants to help their society.
Unfortunately, the lack of literacy keeps the animal's ignorant and misinformed when freedom from Jones is more fully established. The work of the farm is said to become more important and the animal's are told to adopt Napoleon's ways.
Keep in mind that originally, Snowball was the one who set forward on the path to education while Napoleon built his army (the puppies). Snowball was the more scholarly pig (he had the plan for the windmill originally) and as he became the enemy, education fell by the wayside.