Science Experiments: What Can Go Wrong?

It's rarely the kit.

When a science experiment falls flat - the volcano barely fizzes, the crystals don't form, the child loses interest halfway through - the instructions usually aren't the problem. Neither is the concept, or the age, or whether your child is "a science kid."

It's almost always one of a handful of things that are easy to fix once you know to look for them.

Over-preparing

The most common one, and the least obvious. You've read the instructions, laid out the materials, pre-measured everything. Your child arrives and there's nothing left to do but follow your steps.

This backfires because the preparation is part of the experiment. Reading the instructions together, gathering materials, realising halfway through that you need more water - that's not admin, that's the thinking. When you do it all in advance, you've done the interesting part without them.

Prepare with them, not for them. Even if they grab the wrong measuring cup. Especially if they grab the wrong measuring cup.

Hovering

Closely related. "Pour it slower." "That's too much." "Let me do that bit."

Every correction you make is a small signal that they're doing it wrong, which is a small signal that they might do more things wrong, which is a small reason to disengage. Children learn more from pouring too fast and making a mess than from watching you pour correctly.

Step back. Let them spill. Ask what happened afterwards, not instead.

Telling them what will happen

"When we add the vinegar, it's going to bubble up and foam everywhere."

Now they're not discovering anything. They're confirming something you already told them. The moment of surprise - the genuine why did it do that - is gone before it arrived.

Ask them to predict instead. "What do you think will happen?" Then let them find out. A wrong prediction that gets tested is worth ten correct ones that were just handed over.

Only attempting experiments that are guaranteed to work

Real science involves failure and unclear results. If the only experiments you try are the ones you're certain will produce a satisfying outcome, you're accidentally teaching that science is about getting the right answer rather than asking a good question.

When crystals don't form, when the plant in the "good" conditions somehow dies, when the lava lamp is resolutely inert - sit with it. "That didn't work like the instructions said. Why do you think?" Scientists spend most of their time here. So can you.

Rushing to clean up

The experiment ends and you immediately start tidying, asking rapid questions, moving on.

The best thinking often happens in the quiet after. A child staring at the results, poking at something, noticing a detail they missed the first time - this is not them being slow. This is them processing. Sit with the results for a few minutes before anything else happens. Ask one open question and then wait. Really wait.

Not mentioning it again

A good experiment that disappears into the past is a missed opportunity. When something bubbles on the hob, when ice melts in a drink, when a plant turns toward the window - these are the same things you looked at on the kitchen table, and saying so takes about four seconds.

The connections children make between an experiment and the world outside it are often the part that sticks longest. You just have to point at them occasionally.

None of this requires doing experiments perfectly. It requires doing them with enough patience to let the child be the one who figures things out. That's harder than it sounds on a Tuesday evening, but it's the whole thing.

The mess is incidental. The not-knowing-what-will-happen is the point.