The Floss Rule: Meaning, Words, & Multisensory Activity

Posted by Brainspring on 3rd Jan 2016

What is the Double FLSZ Rule?

When we hear /f/, /l/, /s/, or /z/ after a short vowel at the end of a one-syllable word, we double the letters. For example, the word shell is one syllable, has a short vowel, and ends with /l/. Therefore, the letter l is doubled to make “shell”.

Why the FLSZ Rule Matters

Spelling rules play a foundational role in developing reading and writing skills. They impact decoding, word recognition, and writing proficiency. By reinforcing the connections between spoken and written language, spelling rules enhance comprehension and expression.

Examples of the FLSZ Rule

Here are some common examples of words that follow the floss rule:

  • Staff: The word is one syllable, has a short vowel, and ends in /f/, so the f is doubled.
  • Hill: The word is one syllable, has a short vowel, and ends in /l/, so the l is doubled.
  • Pass: The word is one syllable, has a short vowel, and ends in /s/, so the s is doubled.
  • Buzz: The word is one syllable, has a short vowel, and ends in /z/, so the z is doubled.

These examples show how the floss rule works to ensure the correct spelling of these one-syllable words. By recognizing the pattern, students can more easily apply the rule to other words they encounter.

FLSZ Rule Multisensory Activity

The video below highlights not only the spelling rule but also some multisensory activities that can be done to reinforce it. One activity involves having students memorize a mnemonic device. Another one is a card pop activity. For more multisensory ideas, visit Brainspring's Members Area.

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FLSZ Rule Exceptions

The FLSZ rule has some exceptions. It doesn’t apply when the final "s" sounds like /z/, as in "as" or "is." Some specific words, such as "if," "pal," and "gas," are exceptions even though they end in "f," "l," or "s" after a short vowel.

More FLSZ Rule Words:

Puff        Toss        Spill       Mess       Sniff

Shell       Cuff        Press       Bell        Bluff

 Kiss        Drill        Scruff     Chill        Pass

What spelling rules are you interested in learning more about?

Be sure to check back each week for a new spelling rule and activities to teach it!