  In this paper we present a method which aims to improve the spelling of
children with dyslexia through playful and targeted exercises. In contrast to
previous approaches, our method does not use correct words or positive examples
to follow, but presents the child a misspelled word as an exercise to solve. We
created these training exercises on the basis of the linguistic knowledge
extracted from the errors found in texts written by children with dyslexia. To
test the effectiveness of this method in Spanish, we integrated the exercises
in a game for iPad, DysEggxia (Piruletras in Spanish), and carried out a
within-subject experiment. During eight weeks, 48 children played either
DysEggxia or Word Search, which is another word game. We conducted tests and
questionnaires at the beginning of the study, after four weeks when the games
were switched, and at the end of the study. The children who played DysEggxia
for four weeks in a row had significantly less writing errors in the tests that
after playing Word Search for the same time. This provides evidence that
error-based exercises presented in a tablet help children with dyslexia improve
their spelling skills.
