LD Blog

I have robots that search the Web for items about Learning Disabilities. One of them returned a reference to a study published in 2000 that examined the effects of explicit, systematic instruction on spelling performance by students with Learning Disabilities. The study by Craig Darch and colleagues, which appeared in the Journal of Instructional Psychology, provides a good example of how scientifically sound research provides an empirical basis for instruction. Professor Darch and colleagues initially interviewed a small number of students about the ways they approached spelling of words; such small, qualitative studies are informative, but they do not yield results that one can use to guide instruction. However, the reseach team followed that study with a larger-scale study using random assignment of 30 students to groups, repeated trustworthy measurement of spelling performance, and careful control of the instructional conditions. The results of this second study inform practice.

This study reports the results of two experiments which focused on the use of spelling strategies by students with learning disabilities and the relative effectiveness of two different approaches for teaching spelling. In experiment 1, qualitative research method was employed with four elementary students with learning disabilities to document the spelling strategies used during an structured interview, a formal spelling test and an informal writing activity. The data revealed 4 categories of spelling strategies: (1) rule-based, (2) multiple, (3) resource-based, and (4) brute force. Patterns that emerged from the data suggested that students with learning disabilities mostly used inappropriate spelling strategies (e.g., brute force, multiple, resource-based). Based on the results of experiment 1, experiment 2 compared the effectiveness of two highly dissimilar spelling instructional approaches (i.e., rule-based strategy and traditional method) to 30 elementary students with learning disabilities. The results of the experiment 2 showed that students with learning disabilities learned spelling words more effectively when the rule-based teaching and correction procedures were employed in three different probes and one post-test. This study concludes with a discussion of the instructional implications for students with learning disabilities in spelling.

After only 12 lessons, each of which lasted about 20 minutes, the students who received the rule-based teaching spelled significantly more words correctly than the students who received the activity-based teaching. For the technically inclined: Mean number of words spelled correctly was 22 (standard deviation of 2.2) and 16 (standard deviation of 4.3) for rule-based and for activity-based groups, respectively; the difference between the two groups reflects an effect size of ≈ 1.4 (using control s.d.) or ≈ 1.77 (using pooled s.d.), which is a big difference.

The rule-based approach was a commercially available program called Spelling Mastery, an example of a Direct Instruction approach to teaching. It is this sort of powerful instruction that is needed to provide students—whether they have Learning Disabilities or not—with a secure chance to succeed. Faced with evidence such as Professor Darch and colleagues provide (and there’s lots more evidence of this sort), it makes little sense to me for educators to espouse ineffective methods of teaching.

Citation: Darch, C., Kim, S., Johnson, S., & James, H. (2000) The strategic spelling skills of children with learning disabilities: The results of two studies. Journal of Instructional Psychology. 27, 15-27.

Link to the Findarticles archive of the study and a link to Professor Darch’s curriculum vita where one can find references to many other valuable articles, chapters, and books.