Children today greatly lack life skills. So much that there are workshops to teach the basics of life and how to keep oneself alive. Keeping this in mind, we have made a deliberate shift in our parenting to accommodate life skills, science activities and STEM activities.

So now whenever I am setting up a meal, I invite my son to the kitchen and help us. Just a day of observation and my child asked me why onions make us cry. My help, a amazing kind lady, started laughing and said ‘Babu, they help us clean our eyes’. Anyways, I was given a question and honestly I did not know the answer to it. In fact such was my ignorance that I never even tried finding it out, reasoning it. The question had now given me an opportunity to learn while I was trying to be a teacher.

Onions contain Sulphur compounds which make our eyes water. But that’s not all! The chemistry of onions is beyond just that. When we slice or chop the onion, the former stable molecules turn into volatile, sulfur-containing gas. This reacts with the eyes to cause irritation.

Now, our amazing body sets into action to stop this sensitivity. To flush this irritant gas out of our eyes, our peepers start watering. So it is not really the onion! It is our defense mechanism at play! Wonderful, isn’t it? How a simple process of chopping onions triggers our defense mechanism and has so much science behind it. To explain it to your child, you can simplify the process and maybe even omit mentioning Sulphur, unless you want to get that element and show it to your child. I totally did omit it!

Onion Facts


To add STEM and help your child think like a scientist, question her/him how we can avoid these tears? Set up the following simple engaging activity to help your child observe and draw her conclusions.

You will need:

  • Onions
  • Lab/Swimming Glasses
  • Boiling Water
  • Knife
  • Chopping Board

Scenario A: Ask your child to wear lab/swimming glasses and chop an onion. For younger children, ask them to stand next to you while you do the chopping.

Scenario B: Take another onion and place it in the refrigerator and allow it to cool for 10 minutes. Now chop the onion without wearing any eye gear. Did your eyes water again? If yes, did they water as much as they did while chopping an onion at room temperature?

Scenario C: Take a pan of boiling water and put an onion in it for 10minutes. Chop it and compare your finding.

Wearing lab glasses prevent the gases released while chopping to come in contact with eyes. And hence, eyes to not water in this case. Temperature also influences the amount of gas released by the onion and thus a cold onion might not make you cry as much.

Discuss your findings with your child and ask her if she can think of more ways to protect the eyes from watering while chopping an onion. We have always believed that children are truly wonderful and if we an keep their curiosity alive, they are capable of doing anything. Things we don’t question as adults make them curious. And it is only us who dumb them down over years. Hope this activity will help them stay curious.

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