oi, oy, ou, ow

• 2nd grade
• CCSS RF.2.3b

Some vowel teams make a sound that slides from one vowel to another. Teachers call them diphthongs. oi and oy say the sound in coin and boy. ou and ow say the sound in cloud and cow.

What are oi, oy, ou and ow?

Most vowel teams, like ai and ee, make one long vowel sound. These four are different: your mouth moves while you say them. Say "oy" slowly and feel your mouth slide from o to ee. Say "ow" and feel it slide from ah to oo.

There are two sounds and two spellings for each. The sound in boy is spelled oi or oy. The sound in cow is spelled ou or ow. A simple position rule tells you which spelling to use most of the time.

The 2nd grade standard RF.2.3b asks kids to know more vowel teams, and these four are some of the most common. Kids will also see ow make a long o, as in snow, so it gets extra practice.

Which spelling? Middle or end

The position in the word usually tells you which spelling to use.

There are exceptions. Ow is also used before n and l in the middle of words: down, town, brown, owl, growl. When in doubt, write it both ways and pick the one that looks right.

oi, oy, ou and ow in sentences

The vowel team is highlighted.

1. The boy has a toy.
2. I found a coin.
3. The cow is in the barn.
4. A cloud is in the sky.
5. Put the oil in the pot.
6. The owl says hoot.
7. Open your mouth.
8. We enjoy the park.
9. The dog is brown.
10. Don't shout in the house.

Watch out for ow: in snow, grow and show, it says long o instead. If one sound doesn't make sense, try the other.

The two sounds of ow

• ow as in cow: cow, now, how, down, owl, brown.
• ow as in snow (long o): snow, grow, show, slow, bowl, yellow.
• Try both: if the first sound doesn't make a real word, switch to the other.

How to teach oi, oy, ou and ow

Five short steps, about 10 minutes each.

1. Act out the sounds. "Oy!" like you're surprised. "Ow!" like you bumped your toe. Kids remember the sounds with the actions.
2. One sound at a time. Teach oi and oy together, then ou and ow.
3. Middle or end. Sort words by where the sound is: middle (oi, ou) or end (oy, ow).
4. Flex ow. Read ow words both ways: cow and snow.
5. Spell with the rule. Say a word. Ask: is the sound in the middle or at the end? Then choose the spelling.

Common mistakes and how to fix them

Practice: oi, oy, ou and ow quiz

10 questions. Your child can tap the speaker to hear a question read aloud. The first try on each question counts toward the score.

1. 1.Which spelling is right?

   🔈
   boy boi
   Show answer

   boy.

2. 2.Which spelling is right?

   🔈
   coin coyn
   Show answer

   coin.

3. 3.Tap the word with ou.

   🔈

   A cloud is gray.

   Show answer

   cloud.

4. 4.Which word has the same sound as cow?

   🔈
   house snow
   Show answer

   house.

5. 5.Fill in: I have a new t__.

   🔈
   oy oi
   Show answer

   toy.

6. 6.Fill in: Open your m__th.

   🔈
   ou ow
   Show answer

   mouth.

7. 7.Tap the word with oi.

   🔈

   Boil the water.

   Show answer

   Boil.

8. 8.In snow, what does ow say?

   🔈
   long o, like in go the sound in cow
   Show answer

   Long o.

9. 9.Which word has the sound in boy?

   🔈
   oil owl
   Show answer

   oil.

10. 10.Fill in: The dog is br__n.

    🔈
    ow ou
    Show answer

    brown.

oi, oy, ou, ow worksheet (free PDF)

oi, oy, ou, ow Worksheet, 2nd grade

Fill in oi or oy and ou or ow, sort ow words by sound, circle the right spelling and write a sentence. Prints on US Letter paper, with an answer key.

Download the PDF

Try it at home

• Oy! and Ow!: act out the two sounds with surprised and ouch faces.
• Toy box: boy, toy, joy, enjoy: all end in oy.
• Cloud watching: cloud, round, out, about: all have ou.
• Flex ow: read cow and snow and talk about the two sounds.
• Spelling rule: middle or end? Then pick the spelling.

What comes next

Next, kids learn soft c and soft g. Earlier: long or short vowel. See all skills on the 2nd grade page, or browse all phonics lessons.

Last reviewed: November 11, 2026

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