What Is an Idiom
An idiom is a phrase or expression whose meaning cannot be figured out by looking up the individual words. "Raining cats and dogs" doesn't mean actual animals are falling from the sky, and "break a leg" is not a wish for injury. The meaning comes from cultural convention and repeated use, not from the literal definitions of each word.
Idioms appear everywhere in everyday English, making them unavoidable in reading materials from grade 2 onward. Most standard reading curricula introduce idioms formally around grade 3 or 4, though students encounter them implicitly much earlier through listening and reading.
Why Idioms Matter for Struggling Readers
Idioms create a specific comprehension problem for struggling readers, particularly those with dyslexia or language-based learning differences. A student might decode every word in a sentence perfectly (a strength of the Orton-Gillingham method) but still misunderstand the entire message because they're stuck on literal interpretation.
Research shows that students with dyslexia often struggle with idioms longer than their peers because idiom comprehension relies on semantic understanding and cultural knowledge, not decoding skills. For these students, encountering unknown idioms in grade 5 texts can tank comprehension scores even when fluency measures show improvement.
In an IEP context, idiom comprehension is sometimes addressed under "language development" or "vocabulary" goals, though it deserves explicit attention as its own skill.
Teaching Idioms to Struggling Readers
- Direct instruction works best: Don't assume kids will pick up idioms naturally. Teach them explicitly with visual supports. Show a picture of someone's head exploding next to "my head is exploding with ideas" to anchor the literal versus figurative contrast.
- Start with high-frequency idioms: Focus on phrases students encounter in their reading level. "Piece of cake," "under the weather," "spill the beans," and "cost an arm and a leg" appear in texts kids actually read between grades 2 and 4.
- Use context clues strategically: Teach students to recognize when surrounding sentences explain the idiom's meaning. This bridges comprehension and builds independence.
- Connect to figurative language: Once students understand metaphors and similes through phonics and vocabulary work, idioms become one more category of figurative language rather than an isolated concept.
- Create a running list: Keep an idiom reference sheet students can add to throughout the year. Visible, growing evidence of learning motivates continued attention.
Common Questions
- Should I teach idioms before the student can decode fluently? Partially. While decoding must come first, exposure to idioms through read-alouds helps build oral language understanding early. Formal study of idiom comprehension typically begins after a student has solidified decoding at their reading level.
- Are idioms worth including in an IEP? Yes, if the student's comprehension is strong but idiom-specific confusion is noted in assessments. Specific goals might target "identify the meaning of 5 new idioms per week using context and direct instruction" or "distinguish between literal and figurative meanings in grade-level texts."
- Why do some students get idioms and others don't? Exposure, cultural background, and language processing differences all play a role. Students who read more widely, have heard idioms used at home, or have strong semantic language skills pick them up faster. Language-based learning disabilities can delay this skill significantly.