Critics of the "reform" textbooks say that they teach concepts which were once reserved for advanced students in higher grades. Procedural and traditional arithmetic skills such as long division are de-emphasized, or some say nearly totally deleted in favor context and content which has little or nothing to do with mathematics. Some textbooks have a separate index solely for non-mathematics content called "contexts". Reform texts favor problem-solving in new contexts over template word problems with corresponding examples. Reform texts also emphasize verbal communication, writing about mathematics and their relationships with disenfranchised groups such as ethnicity, race, and gender identity, social justice, connections between concepts, and connections between representations.
One particular critical review of Investigations in Number, Data, and Space says:
It has no student textbook.
It uses 100 charts and skip counting, but not multiplication tables to teach multiplication.
Decimal math is "effectively not present".