Unique Words Require Unique Instruction

    Unique Words Require Unique Instruction

    Hiebert, E. H., 2012. Unique Words Require Unique InstructionTextProject & University of California, Santa Cruz

    The Common Core State Standards include a component that has not been included in previous standards documents of either states or national organizations—a staircase of text complexity. The goal of this series of ever-accelerating text levels over students’ school careers is to ensure proficiency with the complex texts of college and the workplace on high school graduation (CCSS/ELA, 2010). One of the signatures of complex texts is the inclusion of low-frequency or rare vocabulary. That means as students take on increasingly complex text, they will need strategies for dealing with unknown words.

    By definition, low-frequency words are rarely encountered by students, which means students have few exposures to them. We refer to them as unique words because, even though there are many words of this type, they make up only 10% of the vocabulary in texts (Hiebert, 2012). In narrative texts, these low-frequency words typically represent new ways of representing a known concept. Many students may not immediately recognize the meaning of the word nonplussed but most know what it means to be confused. In informational texts, the unique words typically represent conceptually complex concepts that are unknown to students and require factual information or a related system of concepts to understand (Nagy, Anderson & Herman, 1987). For example, to understand electrochemical energy requires that students understand terms such as chemical energy, conversion, and electric energy.

    Most individuals could engage in hundreds of conversations and watch numerous television programs or movies without hearing words such as nonplussed or electrochemical energy. Both types of unique words, whether the synonyms for known concepts in stories or the new concepts in informational texts, are usually acquired through academic tasks that include reading, discussion, observation, and experimentation (Cervetti, Pearson, Bravo & Barber, 2006).

    Many techniques are available for helping students to tackle unfamiliar vocabulary in stories, such as suggesting that they substitute a known word that makes sense in the context or use the context of the sentence or paragraph for clues to find meaning (Graves, 2006). These strategies can be useful for the unique words of stories but the theme of this article is that teachers need to make the distinction between the unique words of stories and informational texts explicit to their students. To be proficient with complex texts, students need to know about the ways unique words differ in stories and informational texts. For teachers to teach in a way that uncovers these unique kinds of vocabularies in stories and informational texts, a first understanding involves the 90%/10% distribution in the vocabularies of texts (Hiebert, 2011).

    Distinguishing the Unique Words from the 90%

    The most frequently used words belong to a relatively small vocabulary set that comprises 90% of the words in texts. This word set has a base of 4,000 simple word families, which generates approximately 10,000 words (Hiebert, 2012). With a few important exceptions (e.g., the, a, an), words are part of the core vocabulary because they have multiple meanings. For example, the word energy is an essential concept in physics. But there are many applications of the idea of intensity or vitality of action in other subject areas. Characters in stories are described as full of energy or a newspaper columnist describes an individual as an energetic defender of human rights. The various applications of this concept (in literature, social studies, arts, sciences) add to the word’s frequency and also add to the number of potential exposures a student might have to the word. By contrast, the word electrochemical is also a physics concept but, since it is used only within a particular subject area, students are unlikely to encounter it frequently. So, the difference between the core lexicon with broader application and the unique lexicon with limited application is clear, even though both types of words can be part of academic vocabulary. Beck and her colleagues (Beck, McKeown & Kucan, 2002) frequently describe this difference as Tier 2 (core vocabulary) and Tier 3 (unique vocabulary).

    Many of the words within the core vocabulary are part of extended morphological or word families that include inflected endings, affixes, compound words and idioms/common phrases. All word families do not take the same form as words with Anglo-Saxon roots such as help which is illustrated in Table 1. Words with roots in French and Latin typically take on many more prefixes and suffixes as illustrated by the word family for socio in Table 2. Teaching morphology not only expands vocabulary around a single root but also gives students patterns they can apply to other roots. This helps students build their vocabulary exponentially. The more familiar students are with the words that are in the 90%, the better their base will be for tackling those in the 10%.

    Table 1
    Illustration of a Word Family with Anglo-Saxon Origins: Help
    Inflected EndingsAffixesCompound WordsIdioms and/or Common Phrases
    give (someone) a hand
    need a hand
    lend a hand
    help out
    help yourself
    help yourself to
    I can’t help it
    Table 2
    Illustration of a Word Family with Romance Origins: Socio (Companion)
    SuffixesPrefixesCompound WordsComplex Phrases
    social science
    social criticism
    social democracy
    social mobility
    social studies
    social welfare
    social work/social worker

    Distinguishing the Words Within the Unique 10%

    The unique 10% is made up of two groups: technical words that convey specific concepts in their own subject area and sophisticated literary words. The difference between these two subgroups of unique words is tied to the genres in which they are found. As illustrated in Figure 1, both stories and informational books share a core vocabulary but the unique words in the two genres are different. The nature of these differences can be seen in the two examples in Table 3. Unique words such as sobbed, humiliated, and collapsed in the story give the reader an understanding of how the character was feeling. The unique word in the informational text—magnetism—represents the technical concept that is the focus of the text.

    Figure 1
    Vocabularies of Informational and Narrative Text
    Informational Text
    Words come from particular categories/topics
    Core VocabularyNarrative Text
    Words belong to particular semantic clusters
    Table 3
    Unique Words in a Third-Grade Story and Informational Text
    Text TypeTexts

    How many times had she said that dumb poem? She wanted the earth to open up and swallow her whole. “I can’t remember.” She sobbed.

    Then someone began to applaud. She had seen that done for little kids who messed up. This wasn’t supposed to happen—not to her.

    Feeling humiliated and not knowing what to do, she ran. Bounding offstage, she bolted for the side door and rushed into the parking lot.

    Strong arms caught her just as she collapsed beside the family car. Carolyn. It was Mama who held her tightly. Mama’s voice was as soothing as a warm breeze. You’re going to be fine, daughter. Just fine.

    Informational Text

    Magnets pull objects that are made of certain metals, such as iron. The force that magnets produce is called magnetism. Magnetism can be a pushing or pulling force. Look at the picture below. Notice how some objects stick to the ends of the bar magnets. The ends of the bar magnets are called poles. The objects that are sticking to the poles of the bar magnets are made of iron or have iron in them. The objects that are not sticking to the poles of the bar magnets do not have iron in them.

    Objects stick to a magnet’s poles because that is where magnetism is strongest.

    Words in boldface type are unique words

    The Unique Words of Stories

    Narratives, even fantasy-based, are rooted in familiar concepts. The characters of stories, whatever their form (e.g., animals, machines, or people) have recognizable personality traits. Stories also have familiar plot arcs: rising actions, a turning point, and a resolution. Plots themselves fall into well-worn patterns that readers might recognize such as a hero’s journey with a goal and obstacles or a mystery to be solved. Unknown words in a narrative context are there to provide specificity and texture to a created world that is based on the known world.

    Consider, for example, words around communication. The idea that people speak or talk is something children already know. Children learn through reading that speech can be characterized in different ways: softly, sweetly, sharply, abruptly, and caustically. They learn that silence can have different moods: eerie, peaceful, or awkward. The task when encountering unfamiliar words in a narrative is to find the connection to the known, using information in the story. Students can learn much about life, the world through another’s eyes, the different motives people have behind their actions, and more from reading narratives, yet the story is always grounded in common experience. Because of that ability to make connections, it is possible to understand a story without a deep grasp of unique words, as long as students don’t have to skip over too many of them (Swanborn & deGlopper, 1999). The advantage of learning these words is that they add nuanced understanding to known concepts and they can be transferred to students’ own working vocabularies, either as sight words or words they use in their own writing.

    The Unique Words of Informational Texts

    The purpose of informational texts is to introduce new essential concepts to students’ understanding of the world. The new concepts are carried by unique technical vocabulary. These unique words are expanding the boundaries of particular categories of learning, and the surrounding words provide important context. For that reason students cannot use their existing understanding to approximate the meaning of unfamiliar words in informational texts. The unique words in this kind of text, such as isotope, mitochondria, and igneous, have no synonyms. They are singular terms that encapsulate specific concepts.

    In informational text the vocabulary and the concepts are fused, and there is no way to properly understand the meaning of the text without a solid understanding of the unique, low-frequency words. There is no way to skip over hard words and still maintain a general understanding of the subject-area topic, requiring students to have an understanding of the words to comprehend the content. What is important to note is that students cannot succeed in their subject area studies without a solid working knowledge of these terms. The recommendation to read the definition of such words in the glossary is not the best advice. Teachers need to tailor their vocabulary instruction to fit the properties of these conceptually complex words, as illustrated in the next section.

    Adapting Instruction for Unique Words of Stories and Informational Texts

    Instruction for the Unique Words of Stories

    Descriptive literary words, such as satiated, incandescent, and ennui, often have synonyms that are more commonly known, such as full, bright, and boredom. The more difficult words add shades of meaning or intensity to the known words, so it is important to help students make those connections. The context of the text does not always aid in decoding the exact meaning. For example, “Jason received his grade and was nonplussed.” You can tell from sentence only that nonplussed is a word describing Jason’s reaction. In order to use context, you would have to do a deeper reading of Jason’s character and/or his situation to begin to guess what synonym (confused) might make sense there. As this illustration shows, teaching vocabulary is part of teaching comprehension skills. to teaching the comprehension skills that help student make inferences about unknown vocabulary words. As instructors, we can support these skills by asking questions that will prompt students to think along those lines.

    Teachers can also recommend techniques that target the properties of this subgroup. As noted above, these words tend to branch off known concepts. So, one way to organize this vocabulary is to set a group of synonyms on a continuum of intensity (Figure 2). In this case, the words at either end are likely to be known and the new words form degrees of intensity in between.

    Figure 2
    Introducing Unique Words by Arranging a Group of Synonyms along a Continuum of Intensity Anchored by Core Vocabulary Words

    Words in boldface type are core vocabulary words

    Synonyms can be mapped in other ways, too, such as dividing words into negative and positive connotations, as illustrated in Table 4. The value of these techniques is twofold. First, students will have a finer sense of the word’s meaning when it is put in relation to similar words. Second, since the technique allows for a group of words to be learned together instead of singly, students will be enrich their vocabulary exponentially.

    Table 4
    Positive and Negative Synonyms: Compliment
    Positive ConnotationsNegative Connotations
    butter up

    Instruction for the Unique Words of Informational Texts

    The words used to define technical words, such as hypotenuse, triangle, and angle will belong to the same discipline, so supporting knowledge in that area is very important. Defining hypotenuse as the long side of a triangle only makes sense if you know what a triangle is. The spiraling curriculum shows how concepts circle around and are addressed with greater complexity in regular intervals. It is important that students learn the basic concepts when they are introduced because that knowledge underlies more advanced concepts and that foundation will be needed again and again.

    Often, students are alerted to a technical word in a textbook by its appearance in boldfaced type, cueing them that a glossary definition is available. A definition that is more difficult that the unfamiliar unique word will be of no assistance, unless the text adds an additional embedded definition or cites. When teachers know how technical words related to a concept are interrelated, they can suggest activities that offer student in-depth experiences with the concept. Students can devise an experiment to demonstrate gravity. Students can make a model of a triangle and label the hypotenuse, make a diagram of photosynthesis with arrows and descriptions, or make a map and draw their own lines of longitude. The big idea here is to demonstrate the meaning of these words, as unique concepts within a discipline supported by concepts that are understood. A multi-sensory is experience is best so students can experience the concept, discuss it, record it, write it, and apply it (Cervetti, Pearson, Bravo & Barber, 2006).


    Understanding how to sort vocabulary into groups according to their context and function can help teachers to target the best kind of learning strategies for students. There are many good vocabulary strategies, but some are a more efficient use of instructional time. Using morphology to unlock the relationships between the core words that connect back to 4,000 word families is a great way to teach unfamiliar words that belong to the 90%. Finding ways for students to interact with unique technical words deepens their understanding of the context and underlying concepts. It makes a stronger platform for continued learning in the subject area. Having students map out unique literary words helps students understand the relationship between synonyms and their varying shades of connotations. This mapping technique gives students a surer footing for making specific word choices than they would have if these words had been learned separately. As the new standards challenge students with increasingly complex texts, a strong vocabulary is going to be students’ greatest asset. 


    Beck, I.L., McKeown, M.G., & Kucan, L. (2002). Bringing words to life: Robust vocabulary instruction. New York, NY: Guilford Press.

    Cervetti, G., Pearson, P.D., Bravo, M.A., Barber, J. (2006). Reading and writing in the service of inquiry-based science. In R. Douglas, M. Klentschy, and K. Worth (Eds.), Linking science and literacy in the K-8 classroom (pp. 221–244). Arlington, VA: NSTA Press.

    Common Core State Standards Initiative (2010). Common Core State Standards for English language arts and literacy in history/social studies, science, and technical subjects. Washington, DC: National Governors Association Center for Best Practices and the Council of Chief State School Officers.

    Graves, M.F. (2006). The vocabulary book: Learning and instruction. New York, NY: Teachers College Press.

    Hiebert, E.H. (2011). The 90-10 rule of vocabulary in increasing students’ capacity for complex text. Retrieved from https://textproject.org/frankly-freddy/the-90-10-rule-of-vocabulary-in-increasing-students-capacity-for-complex-text/

    Hiebert, E.H. (2012). Core vocabulary (Text Matters series). Santa Cruz, CA: TextProject. Retrieved from https://textproject.org/teachers/text-matters/core-vocabulary/

    Nagy, W.E., Anderson, R.C., & Herman, P.A. (1987). Learning word meanings from context during normal reading. American Educational Research Journal, 24, 237–270.

    Swanborn, M.S. L., & deGlopper, K. (1999). Incidental word learning while reading: A meta-analysis. Review of Educational Research, 69(3), 261–285.


    Hiebert, E. H., 2012. Unique Words Require Unique InstructionTextProject & University of California, Santa Cruz

    Unique Words Require Unique Instruction