Practice BIO Using a Cereal Box!

When school kicks into high gear, it can be difficult to find the time to dilate with your classmates. And when you do find the time, it can be frustrating to spend half the practice session troubleshooting your technique before even being able to get into the pupil! Luckily, you’re only 20 minutes and couple snips of a pair of scissors away from a handy practice tool to tide you over between real eyeballs. Even now, in my 3rd year at school, I have found myself dusting off my old box of Honey Nut Cheerios to help shake the cobwebs off and practice my scanning techniques.

Things you’ll need:

  1. Medium-size cereal box
  2. High plus (+15-20D) trial lens from your trial lens kit
  3. A sheet of reading material cut to the dimensions of the back side of the cereal box (can be notes from class, or even a retinal photo)
  4. Tape
  5. BIO and BIO condensing lens (20D)
Gather all your supplies!
Gather all your supplies!


  1. Remove (or eat!) cereal in the box.
  2. Cut an 8mm hole into the front of the cereal box – right in the center is perfect.
  3. Tape trial lens inside the box, perfectly centered over the top of the 8mm hole.
  4. Tape reading material to the inside of the back surface of the box.
The hardest part - don't make the pupil too big!
The hardest part – don’t make the pupil too big!

Putting the box to use!

  1. Lay the box down (this simulates a reclined patient).
  2. Focus the light from your BIO through your 20D lens into the 8mm hole.
  3. Scan from one side of your reading material to the other, and watch your skills improve!
This patient never blinks and doesn't mind bright lights!
This patient never blinks and doesn’t mind bright lights!

Special thanks to Pacific’s Dr. Tracy Doll for allowing me to use the information from her cereal BIO handout for this article.

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