Word family
The -ack word family
The answer
The -ack word family is every one-syllable word that ends in the rime ack, said /ak/. Our lexicon has 20 public words in it: 8 with one consonant first, 8 with a blend and 4 with a digraph or silent-letter pair.
What is in this family?
The ack family sits right where students learn ck, so every word in it practices the ck rule: one short vowel, then /k/, spelled ck. It is full of strong action words (crack, smack, whack, snack), which makes it easy to build sentences. Watch two spellings at the start: kn in knack, where the k is silent, and qu in quack, where two letters spell /kw/.
The words, sorted by what comes before the rime
One consonant before the rime
| Word | Onset + rime | Readable after |
|---|---|---|
| back | b + ack | Lesson 44 |
| hack | h + ack | Lesson 44 |
| lack | l + ack | Lesson 44 |
| pack | p + ack | Lesson 44 |
| jack | j + ack | Lesson 44 |
| rack | r + ack | Lesson 44 |
| sack | s + ack | Lesson 44 |
| tack | t + ack | Lesson 44 |
A blend before the rime
| Word | Onset + rime | Readable after |
|---|---|---|
| black | bl + ack | Lesson 44 |
| track | tr + ack | Lesson 44 |
| crack | cr + ack | Lesson 44 |
| snack | sn + ack | Lesson 44 |
| stack | st + ack | Lesson 44 |
| clack | cl + ack | Lesson 44 |
| slack | sl + ack | Lesson 44 |
| smack | sm + ack | Lesson 44 |
A digraph or silent-letter pair before the rime
| Word | Onset + rime | Readable after |
|---|---|---|
| knack | kn + ack | Lesson 98 |
| quack | qu + ack | Lesson 44 |
| shack | sh + ack | Lesson 45 |
| whack | wh + ack | Lesson 50 |
Word ladder: change one sound at a time
Every step is a real word from the list, and each one changes exactly one sound. Say the change aloud before the student writes the new word.
| Step | Word | The change |
|---|---|---|
| 1 | back | start here |
| 2 | hack | change /b/ to /hh/ |
| 3 | lack | change /hh/ to /l/ |
| 4 | pack | change /l/ to /p/ |
| 5 | jack | change /p/ to /jh/ |
| 6 | rack | change /jh/ to /r/ |
| 7 | track | add /t/ |
| 8 | tack | take away /r/ |
| 9 | sack | change /t/ to /s/ |
| 10 | snack | add /n/ |
Rhymes spelled another way
These words rhyme with the family but spell the rime differently, so they belong to other families. Expect students to mix them up when spelling.
| Spelling | Words |
|---|---|
| -ak | yak, flak |
| -ac | sac |
| -aque | plaque |
How do you teach it?
Teach it right after ck is introduced. Start with single consonants (pack, rack, sack, tack), then blends (track, crack, stack, snack, slack), then the trickier starts: wh, sh, kn and qu.
"The family is a-c-k, /ak/. Listen: /s/, /ak/, sack. /t/, /r/, /ak/, track. How many sounds come before /ak/ in track? Two, /t/ and /r/. Now take away /r/. What's left? Tack."
What is the common error, and the fix?
Students write "pak" or "trak" because they hear one sound at the end. The fix is the ck question: is there one short vowel right before /k/? Yes, so ck.
Sort it: a hands-on activity
Give students the rime card ack and onsets on separate cards. They build words and sort them into "one sound before ack" and "two sounds before ack". The kn card goes in the first pile, because the k is silent. Ask them to explain why.
How this list was built
Every word comes from our lexicon of about 19,000 common words, each checked against a pronouncing dictionary and split into spelling units. Words a student meets in our assessments and progress-monitoring probes are left out, so practicing a list never rehearses a test. A family is every one-syllable base word (no suffix, not a compound) whose rime, the vowel unit and every unit after it, has the same spelling and the same sounds, so bead and bread are in different families. Ladders use only words from the list, and each step changes exactly one sound.
"Readable after" is the first lesson in the lesson sequence at which our decodability engine finds every sound-spelling in the word taught; "not taught" means the word has a spelling the sequence does not cover, so it is read with help. You can check your own lists and passages with the free decodable text checker.
Questions people ask
How many words are in the -ack family?
Our lexicon has 20 one-syllable words ending in ack that a student can practice. Words used in our assessments are left out, so a few common words may be missing from the list.
Why is it ck and not k?
The ck rule: when a short vowel stands alone before a final /k/ in a short word, the /k/ is spelled ck. Every word in this family follows it.
What is a word ladder?
A chain of real words where each step changes one sound: swap a sound, add one, or take one away. Students say the change before they write it, which trains them to hear every sound in the word.