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What is dyslexia?

Dyslexia is a specific learning disability that interferes with learning to read and spell. Dyslexia tends to run in families. Studies show that individuals with dyslexia process language differently in the brain. Dyslexia occurs in people of all races, genders, and income levels, and it is not an indication of lesser intelligence. Many people with reading and spelling difficulties have average or above average intelligence.  In fact, some of the world's great achievers are dyslexic.

The common signs of dyslexia include:

  • Family history

  • Difficulty learning to speak

  • Mixing up the sounds in syllables and long words

  • Problems organizing written and spoken language

  • Left-right confusion

  • Difficulty generating rhyming words

  • Difficulty learning alphabet letter names and their sounds

  • Trouble memorizing address, phone number, months in sequence, etc.

  • Inaccurate decoding

  • Slow, halting, dysfluent reading (guesses at words, skips or misreads words, ignores suffixes, cannot sound out difficult words)

  • Letter/number reversals past first grade

  • difficulty remembering sight words and homonyms

  • Retrieval difficulties and use of non-specific language (things, stuff)

  • Poor spelling and writing

  • Difficulty learning a foreign language

  • Difficulty memorizing number facts

  • Difficulty with math operations

  • Poor grades despite good intelligence

  • Dyslexia is sometimes accompanied by dysgraphia, or difficulty with handwriting and written language

The following formal definition was adopted by the Board of Directors of the International Dyslexia Association (IDA) on Nov. 12, 2002. It is also used by the National Institute of Child Health and Human Development (NICHD):

Dyslexia is a specific learning disability that is neurological in origin. It is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede the growth of vocabulary and background knowledge. 

What is dyslexia?: About

If we screen children in the earliest grades, we can identify RISK FACTORS, intervene appropriately, and PREVENT reading failure.

Screening is fundamental. Check out Dr. Nadine Gaab's article: Let's identify risk instead of failure and her video below.

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The Reading Failure Prevention Model

What is meant by screening? What is being measured?

Standardized, valid screeners assess children on basic pre-literacy and literacy skills. Research indicates that kindergarten screening measures are most successful when they include assessments of phonological awareness including phoneme segmentation, blending, onset/rime; rapid automatic naming (RAN); letter-sound association; and phonological memory, including non-word repetition (Catts, et al. 2015; Jenkins & Johnson, 2008). To learn more about screening tools, check out this list of screeners (and the disclaimer section; DD-DC makes no endorsements).

Screening should be brief, comprehensive, resourceful, early, ESL/dialect inclusive, and developmentally appropriate.

Who should be screened, and when?

Since research has shown that the rapid growth of the brain and its response to instruction in the primary years make the time from birth to age eight a critical period for literacy development (Nevills & Wolfe, 2009), it is essential to identify the instructional needs of struggling students as early as possible. There is no one test that measures all reading skills. When multiple measures are used to screen students, the accuracy of identifying those at risk improves significantly.  

DD-DC advocates for the screening of all K-3 students. Measures, depending on grade level, would include phoneme awareness --specifically phoneme segmentation, blending, and manipulation tasks; letter naming fluency; letter-sound association; phonological memory, including nonword repetition; oral vocabulary; word recognition fluency (including real and nonsense words); oral reading fluency; and reading comprehension, among others. 

What if a problem is detected?

DD-DC is advocating for appropriate interventions if screening results show that a student is at risk for reading difficulties. We believe schools should conduct an informal diagnostic assessment to further establish areas of need, and determine where to begin instruction. Next, schools should provide supplemental reading instruction and monitor progress at regular intervals.

What constitutes an effective reading and spelling intervention?

Depending on the areas of need, students at  risk for reading difficulties should receive instruction in the following areas:

  • Phonological awareness, including phonemic awareness

  • Sound-symbol association (phonics)

  • Sound blending techniques

  • The six syllable types of English

  • Rules for dividing multi-syllable words into individual syllables

  • Spelling rules and patterns

  • Explicit instruction in letter formation for handwriting mastery

  • Study of roots, prefixes, and suffixes (morphology) for spelling and vocabulary growth

  • Parts of speech, grammar and syntax

  • Vocabulary

  • Synonyms, antonyms, multiple meanings and idioms

  • Structured approaches to written expression

  • Fluency and comprehension strategies


Selected intervention programs should include these components as consistent with the International Dyslexia Association's Knowledge and Practice Standards.


Instruction should be robust in its scope, explicit and systematic, taught with fidelity, and oriented toward student mastery.


What is dyslexia?: FAQ

They can't teach
what they don't know

Teachers deserve the knowledge and skills they need to improve student outcomes

Despite the best efforts of DC's dedicated, well-credentialed teachers, roughly three-quarters of school children read below the level of proficiency, as evidenced by PARCC and NAEP scores. In some schools,  the majority of students fall below the basic level, meaning they are functionally illiterate and inclined to drop out of school. 


While the reasons for reading failure are complex and varied, more can be done to enhance reading instruction in our schools. The ubiquitous 'whole language' or 'balanced literacy' methods of reading instruction, while rightfully stressing rich literature and comprehension, generally pay inadequate attention to the crucial foundational aspects of pre-reading and reading acquisition, such as phonological and phonemic awareness, comprehensive phonics, handwriting, and orthography (spelling). In these balanced literacy classrooms, children are taught, through repeated readings, to essentially memorize words so as to be able to recognize them later in other contexts. It is not surprising that students fall behind, especially when the increasing demands of the classroom tax their limited sight vocabulary, and they lack the decoding strategies and knowledge of language conventions that would allow them to read words of any length or complexity.


DD-DC advocates for the training of school teachers in evidenced-based structured literacy practices. We advocate for the hiring of new teachers who have received certification in a structured literacy program accredited by the International Multisensory Structured Language Education Council (IMSLEC) or meet the Knowledge and Practice Standards For Teachers of Reading established by the International Dyslexia Association. 

Armed with a more robust skillset, teachers can meet the needs of DC's struggling readers.

What is dyslexia?: Text

Glossary of Terms

Alphabetic  Principle - The concept that letter and letter patterns represent the sounds of a spoken language.

Automaticity - The ability to respond or react without attention or conscious effort. Automaticity in word recognition allows full energy to be focused on comprehension.

Background knowledge - The prior knowledge a student brings to a reading task.

Comprehension - Making sense of what is read. Comprehension depends on good word recognition, fluency, vocabulary, background knowledge, and language ability.

Controlled decodable text - Text that is written with 95% to 100% of the words already taught, either through explicit instruction in word structure or by memory as a high-frequency sight word.

Cumulative - Describes instruction that is presented in a sequence that begins with the simplest skills and concepts and progresses systematically to the more difficult.

Decode - To break the phonic code (or to recognize a word); to determine the pronunciation of a word by noting the position of the vowels and consonants.

Diagnostic and prescriptive instruction - Instruction in which students are engaged in components of the lesson while the teacher observes how students are handling the discrete components so that the teacher may plan instruction. The prescriptive part of the lesson; may involve changes to permit additional practice, review, and or multi-sensory activities.

Dyscalculia -  A specific learning disability in learning and understanding mathematical concepts.

Dysgraphia  - Extremely poor handwriting or the inability to perform the motor movements required for handwriting. This condition is associated with neurological dysfunction.

Executive function difficulties - Difficulties with certain cognitive skills such as poor planning, disorganization of time and materials, difficulty narrowing a topic in writing, and procrastination.

Explicit instruction - teaching a specific skill step-by-step, also known as direct instruction.

Fluency - Reading words at an adequate rate with a high level of accuracy, appropriate expression, and understanding.

Grapheme - A written letter or letter cluster representing a single speech sound.

Graphomotor - Pertaining to the skillful coordination of the muscle groups involved in handwriting.

Individualized Education Program (IEP) - A document that sets out the child’s placement in special education as well as the specific goals, short-term objectives, and benchmarks for measuring progress each year. Creating and implementing the IEP must include the opportunity for meaningful participation by the parents.

Individuals with Disabilities Education Improvement Act (IDEA) of 2004 reauthorized in 2015 as Every Student Succeeds Act - Special-education legislation originally passed in 1975 and amended in 1990 and 1997 that serves as a mechanism to help fund special education. This legislation mandates that states receiving federal monies must provide special education and other services to qualify children (from birth through age 21) with disabilities or risk the loss of these dollars. IDEA 2004 protects a child’s right to a free appropriate public education (FAPE) in the least restrictive environment (LRE).

Irregular word - a word that has an unexpected spelling because either it’s orthographic representation does not match its pronunciation, or because it contains an infrequent orthographic representation of a sound.

Language-based learning disability -  Defined as a disorder in one or more of the basic processes involved and understanding or producing spoken or written language.

Matthew Effect - A term coined by Stanovich (1986) to describe a phenomenon observed in findings of cumulative advantage for children who read well and have a good vocabulary and cumulative disadvantage for those who have adequate vocabularies and read less and thus have lower rates of achievement. The term is named after a passage from the New Testament: "For unto everyone that hath shall be given, and he shall have abundance: but from him that hath not shall be taken away even that which he hath" (Matthew 25:29).

Morpheme -  the smallest meaningful linguistic unit. A morpheme may be a base word or root, a suffix, or a prefix.

Morphology - The internal structure of the meaningful units within words and the relationships among words in a language. The study of word formation patterns

Norm-referenced assessment or test -Assessment of performance in relation to that of the norm group (cohort) used in the standardization of the test. Norm-referenced tests produce scores that permit comparisons between a student and other children of the same age or grade level. All norm-referenced tests are standardized.

Onset - The initial written or spoken single consonant or consonant cluster before the first vowel in a syllable. 

Orthography - The writing system of a language. Correct or standardized spelling according to established usage.

Phoneme - The smallest unit of speech that makes one word distinguishable from another in a phonetic language such as English.

Phonemic awareness - Awareness of the smallest units of sound in the speech stream and the ability to isolate or manipulate the individual sounds in words. Phonemic awareness is one aspect of the larger category of phonological awareness.

Phonics - The paired association between letters and sounds; an approach to the teaching of reading and spelling that emphasizes sound-symbol relationships, especially in early instruction.

Phonological awareness -The sensitivity to the sound structure in spoken language. Phonological awareness progresses from rhyming; to syllable counting; to detecting first, last, and middle sounds; to phonemic awareness, which includes segmenting, adding, deleting, and substituting sounds in words.

Phonological processing - The ability to perceive, understand, and use the sound structures of words in both oral and written language.

Pre-literacy - Early experiences with skills associated with learning to read, such as singing the alphabet, identifying letters, playing with rhyming words, and understanding the difference between a word and an image in a book.

Prescriptive - When used in the context of instruction, entailing the changes made to a lesson to tailor it for more practice, review, and/or multi-sensory activities.

Print-rich environment - An environment filled with many varieties of printed materials used for multiple purposes, including non-academic purposes.

Progress monitoring assessment - An assessment used with students identified as not meeting learning expectations who participate in specialized instruction to help them develop needed skills. Progress monitoring tasks are administered after short intervals of instruction. Their purpose is to measure students’ learning and determine the impact of the instruction.

Rapid automatic naming (RAN) - A speed naming task, most often administered to pre-readers, in which the individual is asked to quickly name a series of printed letters, numbers, or blocks of color repeated in random order.

Response to intervention (RTI) - An integrated model of assessment and intervention with a multilevel prevention system to identify students at risk as well as monitor their progress, supply evidence-based interventions, and allow for appropriate adjustments based on student responsiveness. An alternative way to identify students with learning disabilities.

Rime- The vowel and the consonant(s) after the vowel in a written or spoken syllable.

Screeners - Broad-based assessments designed to identify students who have developed expected skills to an established benchmark and those who have not.

Sequential - In structured literacy education, the orderly presentation of linguistic concepts based on frequency and ease of learning in a continuous series of connected lessons.

Sight word - A word that is immediately recognized as a whole and does not require decoding to identify. A sight word may or may not be phonetically regular.

Structured literacy - Instructional approach that incorporates systematic, cumulative, explicit, and sequential approaches taught by teachers trained to instruct language structure at the levels of sounds, syllables, meaningful parts of words, sentence structure, and paragraph and discourse organization.

Syllable - a spoken or written unit that has a vowel or vowel sound and may include consonants or consonant sounds that proceed or follow the vowel. Syllables are units of sound made by one opening of the mouth or one impulse of the voice.

Syllable division - The process of breaking multisyllabic words into separate syllables using a reliable pattern to aid pronunciation.

Syllable types - Orthographic classifications of syllables. There are six syllable types in English: closed, open, vowel-consonant-e, vowel pair, vowel-r, and consonant-l-e (final stable syllable).

Whole language - A perspective on teaching literacy based on beliefs about teaching and learning that include the following: reading can be learned as naturally as speaking; reading is focused on constructing meaning from text using children’s books rather than basal or controlled readers; reading is best learned in the context of the group; phonics is taught indirectly during integration of reading, writing, listening, and speaking; teaching is child-centered and emphasizes motivation and interest; and instruction is offered on the basis of need.

Written language disorder - A disability that involves impairment in reading, decoding, sight word recognition, reading comprehension, written spelling, and/or written expression. Written language disorders, as with spoken language disorders, can involve any of the five language domains (phonology, morphology, syntax, semantics, and pragmatics).

*From Multisensory Teaching of Basic Language Skills, by Judith Birsh, et al. 

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