Mathematical lies we tell students

  • Mathematical lies we tell students

    Christy Danko Graybeal, Ph.D.
    With the best of intentions, many teachers find themselves telling students mathematical fibs. We say these half-truths to avoid giving complicated explanations, but children take our statements as absolute truths, and this can lead to misconceptions. What follows is a list of some of the most common “mathematical lies” with explanations for why each is not an exact truth. The Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010) call on students to attend to precision (Standards for Mathematical Practice [SMP] 6), and we teachers must do the same by carefully considering our word choices so as to avoid misleading students.