What to Do When Your Child's Science Experiment Fails

The volcano barely fizzed. The crystals never grew. The paper plane nosedived every time. If you have ever watched a child’s face fall when an experiment “didn’t work,” you are in good company, and you are in the right place for the real science to begin.

Real scientists have experiments that do not work all the time. What matters is what they do next. You can teach that skill at the kitchen table.

First, change the word

Try not to say “failed.” Say:

“That’s not what we expected. Interesting.”
“We got a result. Let’s work out why.”
“That is data.”

An unexpected result is information. It tells you something about your materials, your method or your idea.

A calm first response

Children pick up your reaction. Take a breath, smile and say, “Okay, detectives. What do we notice?” Then slow down:

Describe it. What exactly happened? What did you see, hear, smell (no tasting)?
Compare it with what you predicted. What did you think would happen?
Don’t fix it yet. Write down what happened in the notebook before anything changes.

A troubleshooting checklist

Go through these one at a time. Change only one thing before you try again.

Did we follow the steps in order? It is easy to skip one.
Are the amounts right? Check measurements. A little too much or too little can change the result.
Are the materials the right kind? Baking soda is not baking powder. Table salt is not Epsom salt. Fresh and old yeast behave differently.
Is the temperature right? Many experiments depend on warm or cold. Adults should handle any heating.
Did we wait long enough? Crystals, seeds and ice take time.
Was the test fair? Did we change more than one thing at once?
Was the measuring reliable? Could we measure again and compare?
Was it set up on a surface that is level, still and clean?

Turn it into a second experiment

A surprising result is often the beginning of a better question.

“The balloon rocket went nowhere. What if the string is tighter? What if we use a bigger balloon? Which one do we change first?”

Pick one change, predict, test again, and record both results side by side. Compare the two attempts. Children learn more from a pair of results than from one that worked.

Things that can really go wrong

Some “failures” come from the experiment itself, and that is normal:

Small variations in a home kitchen: humidity, room temperature, ingredient age
Instructions written for ideal conditions
Measurements that are hard to read by eye
Experiments that work most of the time but not always

It is perfectly fine to say, “I’m not sure what went wrong. Let’s guess and test.” You do not need to be the expert. Looking something up together is part of the lesson.

When to stop

Some days, children are tired or upset. Stop. Write down the question and say, “We’ll come back to this tomorrow.” Do not push through a meltdown. An experiment can wait; the relationship with learning cannot.

What children learn from this

Results are not good or bad; they are information
You can change one thing and try again
It is normal not to know the answer yet
Mistakes can be interesting rather than embarrassing
Writing things down helps you think

Safety when you repeat an experiment

Do not add more of a chemical in hope it will work better, and never mix cleaning products. Do not eat or drink experiment materials. Keep adults in charge of heat, sharp tools and anything unfamiliar.

Where to go next

Read more in why science experiments fail and what to do, pick up good questions to ask during an experiment, and try a quick activity from the Build and Launch unit where retrying is built in.