The "Parrot Math" Attack on Memorization

Constructivist math educators regularly cite Parrot Math by Thomas C. O'Brien. Although this paper promotes constructivist "activity-based" learning over direct instruction, it's primary claim to fame is the open hostility to memorization. Professor O'Brien rejects "memorization and parrot-like drill " in favor of "children's invented strategies." He references a paper by Kamii and Dominick as evidence of "considerable research" showing that mastery of the standard algorithms of arithmetic is harmful for children. [See The Bogus Research in Kamii and Dominick's Harmful Algorithms Papers]