My child is 2.5 years old and he and I regularly discuss book reviews. I don't understand the reason of doing this, it seems quite acward. I also think you should never under estimate somebody. But, in this case you're over estimateing first graders. What is really ubsurd is that you say that preschool and kindergarten can also do this activity.
Children consume TV, movies, and books.
My child is 2.5 years old and he and I regularly discuss book reviews.