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Thoughts About Reading

Sight Words? High Frequency Words? Heart Words? Irregular Words? It's so confusing!

Updated: Sep 29, 2023

If you are a parent of an elementary child or even a teacher, you might have heard the phrases "sight words, high frequency words, heart words, and irregular words" and wondered what the difference is. For a long time, these terms have been used interchangeably to mean words that we can't sound out and have to know by memory or by heart.

My new favorite saying as an educator who is diving deep into the Science of Reading and learning how our brains learn to read is "I didn't know! Now I do, so now I do better!" This little saying keeps me from feeling guilty about what I didn't know in the past about teaching reading and excited about what I am able to teach my students now.

The difference between what each of the above phrases is referring to is one of those things that I didn't know in the past but now I do, and I love what I am seeing as result of it. Many parents and teachers are familiar with the terms "sight words, HFW, or heart words" You may have even heard the phrase"irregular words" being used more and more in instruction. For a long time we have just lumped all of these terms into one pot referring to words that have to be memorized or recognized by sight, because they do not follow a pattern that can be sounded out or easily decoded. Let's define each of these terms to help us as parents and teachers of young readers know the difference and understand what the research in reading is says about these types of words.

Sight Words- A sight word is any word that a a reader knows by sight or does not have to spend brain energy on trying to decode and figure out. High frequency words, vocabulary words, technical terms, or any word that the reader cannot read with automaticity is not a sight word. Once the word crosses over into the readers's lexicon and becomes a word that can be decoded instantly with automaticity, it becomes a sight word for that reader. This is backwards to what some of us were taught. In the past, we have used this term to refer to words that the reader had to know by sight due to not being fully decodable. An example of this would be the word, "said." If the child is having to sound out the word to try and read it, it is not a sight word. However, if he/she is able to just read the word automatically, it is a sight word. The bottom line with this is that every student will have a bank of sight words that is unique to his/her own reading development and capabilities. This is our goal in reading have each of our students increase the amount of sight words stored in their lexicon so that automaticity and fluency are achieved and comprehension is not compromised.

High Frequency Words- HFW are those words that we see a lot of when reading. Hence the the term "high frequency." These are the Fry words and Dolsch Words. These can be sight words for a reader or not, but we do see them a lot when we read. I have read articles of reading researchers that say anywhere from 60%-80% of the words that we read in a text will be high frequency words. Whether it is 60% or 80% is not what matters. The fact is that both of these are very high percentages of what we are reading, and it would serve a reader well to have these words as part of his/her sight word bank. If a reader does not have to spend time and reading energy on the HFW when reading, it leaves more brain power to use on the other words that may not be read by sight like new vocabulary words. It also allows readers more time to focus on the story as a whole which aids in comprehension.

Heart Words- Just like the term "sight words," the term "heart words" has been used in the past to describe words that the reader has to know by heart in order to read, because it is not easily decodable. This is not entirely true. If you look at many high frequency words, you will notice that many of them can be decoded and most of them only have a part of the word that does not follow a phonics pattern. Words that have a part or parts that can't be decoded are considered irregular words meaning that some part of the word is "irregular" and has to be known by heart. For example, the HFW "had" is 100% decodable so therefore not an irregular word, but the word "said" is irregular because the /ai/ does not follow the phonics rule for vowel teams and therefore has to be known by heart. This is huge for young readers. When taught this skill, the reader has a way to attack irregular words by breaking them down into decodable and non decodable parts. This builds confidence and makes the task of reading unknown words and even multisyllabic words less intimidating and more manageable. It also discourages guessing which we do not want our readers to do.

Click here to read about the importance of not letting our students guess at unknown words.

Click here to see a short demonstration of how to identify the irregular part of a word using the heart method.

In summary, it is important for us as teachers and parents to use these terms correctly as well as teach them to our students. This helps them to not be confused, to categorize word parts into those they know and don't know, and gives them a way to attack unknown words that makes sense to them and is tied to the phonics skills already learned.

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