The Source Test
Before your child believes anything, teach them to ask two quiet questions: who is saying this, and how could they possibly know?
The Source Test is a simple habit of pausing before you accept a claim to ask where it actually came from. Every fact arrives attached to a person or a system, and that origin tells you a lot about how much weight the claim deserves.
The mental move has two parts. First, identify the source: who is making this claim? Second, test their access to the truth: how could that person possibly know it, and do they have a reason to shade it? A weather forecaster has instruments and training. A kid repeating a rumor on the bus has neither.
Why it matters
Children now swim in claims from people they will never meet: ad copy, viral videos, AI-generated answers, and classmates passing along things they half-heard. None of it comes with a built-in honesty label. A child who reflexively asks who said this and how they would know has a filter that works on a TikTok clip, a homework search result, and a salesperson alike. It is the difference between a mind that absorbs whatever floats by and one that decides what gets in.
How to use The Source Test with your child
- Name the source out loud. When your child shares a claim, ask them simply: who told you that? Getting them to name the actual source is half the work.
- Ask how they could know. Together ask whether that source is in a position to actually know this. Did they see it, measure it, or are they just repeating it?
- Check for a reason to bend it. Ask whether the source gains anything if you believe them. A company selling a toy and a friend who saw the toy break have very different stakes.
- Rate your confidence. Land on a verdict together: solid, shaky, or worth checking elsewhere. Naming the confidence level keeps belief from being all-or-nothing.
See it in action
Ten-year-old Marcus comes home certain that a new energy drink makes you smarter because a YouTuber said so. Instead of arguing, his dad asks the two questions. Who said it? A YouTuber. How could he know it makes you smarter, and does he gain anything? Marcus pauses, then realizes the channel was paid to promote the drink and the man never tested anyone. By the end Marcus has not just dropped one claim, he has practiced a move he will use on the next hundred.
By age
Keep it to one question, who told you that, and treat it like detective work rather than a quiz.
Add the second question about how the source could actually know, and let them spot when someone is just repeating a rumor.
Bring in incentives and expertise, asking what the source gains and whether they are actually qualified to know.
Frequently asked questions
Isn't this just teaching my kid to distrust everything?
No, the goal is calibrated trust, not blanket suspicion. The Source Test helps a child believe reliable sources more confidently while catching the shaky ones. Over time it actually makes them better at trusting the right people.
My child says I should trust them, so isn't questioning sources rude?
There is a difference between doubting a person and asking how they know something. Frame it as checking the claim, not the kid, and apply it to yourself too. When you model questioning your own sources, it stops feeling like an accusation.
What if the source is a teacher or a textbook?
Those are usually strong sources, and the test confirms that rather than undermining it. You can note that teachers and textbooks are built to be checked and corrected, which is exactly why they tend to be reliable. The point is the habit of asking, not assuming any source is automatically wrong.
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