Throughout the 2oth century, many second year Latin books based their content upon Caesar's Gallic Wars. It is clear that for over a century, Latin teachers and professors have dealt with the question of the place of Caesar's writings in the Latin curriculum.
As early as 1916, Josiah Bethea Game wrote in Teaching High School Latin: "Classes are often not ready for Caesar at the opening of the second year...Caesar is more difficult Latin than its place in the course of study would indicate...It really ought to be given in the third year, for it is the rock on which unnumbered thousands of faithful pupils have gone to pieces utterly." (p. 76)
Moving Caesar to Advanced Placement status may at least allow teachers to finally admit that Caesar is actually quite difficult for second year students.
Another criticism of Caesar is that his material is actually fairly dry and dull.
Game spends most of his time in the chapter discussing second year Latin on how to teach Caesar effectively, admitting that "if you work under a course of study which absolutely fixes the work in Caesar, you will of course be forced to do the best you can." He notes that students don't usually learn much about Roman civilization in a Caesar course and that it is imperative that they spend time reading something other than Caesar or they may end up "feeling that Latin is of limited value." He strongly suggests that students prepare contextual themes to present to the class in order to provide coherence to the course.
Charles Bennett (perhaps the greatest champion of the grammar-based philosophy of teaching Latin) even conceded the weaknesses of Caesar while continuing to support his placement in the curriculum.
He enumerates several objections to Caesar (and especially De Bello Gallico) in The Teaching of Latin and Greek in the Secondary School (1911): "a) Caesar is undeniably difficult...b) Caesar is not interesting," and "c) the bearing of Caesar's narrative is not obvious," (pp. 112-113) summing it all up thus: "Caesar...is regarded by many as unique in its combination of difficulty, its dullness and its dearth of information." However, Bennett ultimately concludes that there is value in reading Caesar's Latin for his "purity of diction" and "accuracy of style" (p. 114.)