How to Teach Heart Words Using the Science of Reading

How many times have you had a student get stuck on a high frequency word — even after repeated exposure?

You practiced “was” all week. Flash cards. Read it in context. Reviewed it again.

Then your student sees was and says:

/w/ /a/ /s/

Back to square one.

If this sounds familiar, you are not alone. And here’s the good news:

High frequency words do not need to be memorized.

They need to be mapped. 

The heart word method is a Science of Reading aligned approach that teaches students how to orthographically map sight words instead of relying on rote memorization.

Why Memorizing Sight Words Doesn’t Work

For years, sight words were taught through repetition and visual memorization.

But research shows skilled readers do not memorize words by sight alone. They use orthographic mapping — connecting sounds (phonemes) to letters (graphemes) and storing those connections in long-term memory.

This means high frequency words must be connected to phonics instruction.

Even irregular words can be partially decoded.

What Are Heart Words?

Heart words are high frequency words that contain at least one irregular sound-spelling.

Instead of memorizing the entire word, students:

• Sound out the regular parts
• Identify the irregular part
• “Heart” only the tricky portion

This keeps instruction aligned to structured literacy principles.

Permanent Heart Words

Permanent heart words are permanently irregular. They contain spellings that do not match typical phonics patterns.

Examples:

• one
• two
• of
• been

These words require explicit instruction because their spellings are unique.

Did you know that 100–200 high frequency words account for nearly 50% of the words students encounter in school texts? Approximately 25% of those are permanently irregular.

Explicit instruction matters.

Temporary Heart Words

Temporary heart words are only irregular based on a student’s current phonics knowledge.

Example: too

If students know:
• t = /t/

But have not yet learned:
• oo = /oo/

Then oo becomes the heart part.

Once that phonics skill is explicitly taught, the word becomes fully decodable.

This is why heart word instruction must align with your phonics scope and sequence.

What Are Flash Words?

Some high frequency words are completely decodable. These are often called flash words.

Examples:

• let
• him

There are no heart parts in these words (assuming students have been taught the sound-spellings).

Students still need practice with these words to build fluency and automaticity.

Why the Heart Word Method Works

The heart word method supports orthographic mapping.

Students:

• Say the word
• Segment the sounds
• Map phonemes to graphemes
• Identify the irregular part
• Store the word in long-term memory

This is how the brain builds automatic word recognition.

It is structured literacy.
It is explicit.
It is Science of Reading aligned.

Science of Reading Aligned Heart Word Practice

A structured heart word routine might include:

• Saying and rereading the word
• Identifying each sound
• Writing the letters that match each sound
• Drawing a heart around the irregular part
• Reading the word in a sentence

This approach builds automaticity without relying on memorization.

Frequently Asked Questions About Heart Words

Are heart words the same as sight words?
Heart words are high frequency words taught using phonics and orthographic mapping rather than memorization.

What is the difference between heart words and high frequency words?
High frequency words are common words in text. Heart words are high frequency words that contain irregular parts that must be explicitly taught.

Are heart words aligned to the Science of Reading?
Yes. The heart word method aligns with structured literacy and orthographic mapping research.

High Frequency Word Tools and Resources:

High frequency words do not need to be memorized. They need to be explicitly taught and mapped. When we align sight word instruction to phonics, we build confident, automatic readers.

If you are looking for structured, Science of Reading aligned heart word practice, these resources provide explicit instruction in high frequency words and sight words using the heart word method:

• UFLI Aligned Heart Word Practice Slides and Flash Cards for modeling and whole group instruction
• Heart Word Practice Worksheets for Kindergarten, 1st, and 2nd Grade for hands-on orthographic mapping practice

These tools support students as they map sounds to spellings and build automatic recognition of high frequency words.

If you’re ready for a complete, structured literacy system that supports phonics, heart words, decodable reading, sentence writing, and comprehension, you can explore Literacy Unlocked — my K–2 Literacy All-Access Club.

Inside, you’ll find systematic, evidence-based resources designed to help you move students from sounds to comprehension with confidence.