The Collaborative International Dictionary of English v.0.48:

Misteach \Mis*teach"\, v. t. [imp. & p. p. Mistaught; p. pr. &
   vb. n. Misteaching.] [AS. mist[=ae]can.]
   To teach wrongly; to instruct erroneously.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "misteaching":
   abstractionism, coloring, deformation, distortion, exaggeration,
   expressionism, false coloring, falsification, garbling, hyperbole,
   inaccuracy, injustice, litotes, miscoloring, misdirecting,
   misdrawing, miseducative, misguiding, misinforming, misinstructive,
   misleading, mispainting, misquotation, misreport,
   misrepresentation, misstatement, nonrealism, overdrawing,
   overstatement, perversion, slanting, twisting, understatement