Printable Diphthongs Worksheets

Printable diphthongs worksheets for 2nd and 3rd grade, with an answer key on every sheet. The sets below cover 2 different skills, so you can start where your child actually is. Available as fill in the blank and sorting activities.

About Diphthongs

What this skill is

Diphthongs cover complex vowel sounds where mouth shape glides (oi/oy in coin/toy, ou/ow in house/cow, au/aw in fault/saw).

When children learn it

Diphthongs are taught in 2nd and 3rd grade, aligned to 2.RF.3.B.

Teaching Tips

  • Notice mouth shape changes while pronouncing gliding diphthong sounds.
  • Remember that oy usually comes at word ends while oi appears inside words.

Common Mistakes

  • Confusing ow in cow (diphthong) with ow in snow (long o).
  • Misspelling oi at word ends where oy is required.