As parents, we all want to raise confident, fearless and resilient kids. But where do we begin?

For my book, "Raising an Entrepreneur," I talked to 70 parents who raised highly successful people. When I asked them what skills they taught their kids at an early age, there was one in particular that they all agreed on: curiosity.

Curiosity goes further than a simple desire to know something. It involves trying to fix something. It's about asking questions: How does this work? Does it have to be this way? Could I make it better?

How to teach your kids to be more curious

Surprisingly, curiosity is a rare skill these days. Career experts even call it an "up-and-coming skill," and Harvard Business School researchers named it as a highly sought-after trait in the digital era.

Curiosity allows for one to think more deeply and critically, without judging too quickly, and arrive at more creative solutions. 

Here's how the parents I interviewed nurtured curiosity in their kids:

1. They encouraged their kids to fix things.

When he was 24, Robert Stephens founded Geek Squad, a technology repair company that he later sold for $3 million.

Robert's curiosity for how things worked started when he was a young boy, when he unscrewed all the doorknobs in his parents' house. "They weren't angry, they just said I had to put them back," he told me.

He soon became known as the "fix it" guy in the family. "I took apart a radio to study it. People would say, 'Robert can fix anything.' It gave me a sense of pride and self-esteem."

Fixing things can help kids develop decision-making and problem-solving skills. If you have something around the house that needs repairing, like a bad lightbulb or leaky faucet, use it as a teaching opportunity with your kids.

It's also okay to admit if you're unsure how to fix something. Knowing where to find accurate information is just as important as knowing it from the start.

2. They instilled the confidence to tackle big, real-world problems.

Jessica Jackley is the co-founder of Kiva, a peer-to-peer lending platform that has lent more than $1 billion in microfinance loans to small businesses.

"My mom built my confidence every single day. She told me I could do anything I wanted to do, no matter how unachievable and ambitious it seemed. And in very specific ways we would talk about different leadership opportunities," she said.

They also had a rule to never be bored. "We were always learning things together, playing games, exploring or having little adventures. This spirit prepared me to be an entrepreneur — to be proactive and see opportunities in the world."

3. They asked the hard questions.

Ellen Gustafson co-founded FEED Projects in 2007, which sells bags and other items to raise money for school meals. Today, she's a thought leader on social innovation.

Ellen's mom Maura credits much of her daughter's success to one parenting rule: "Resist the temptation to make choices for your kids."

Instead of always telling Ellen what to do, Maura encouraged her to be independent and think for herself. "The best way to do that is by asking them questions," she said.

For example, let's say your child went outside during a lightning storm. You could ask them:

• "You put yourself in a very risky situation. How did you analyze it?"
• "What made you decide to do what you did?"
• "Is there anything you learned from this experience that would make you evaluate risk differently next time?"

Smart questions show that you respect your kid's judgment, which builds their confidence. It also teaches them how to manage risk and how to make choices among different possibilities with various trade-offs and different outcomes.

Margot Machol Bisnow is a writer, mom and parenting expert. She spent 20 years in government, including as an FTC Commissioner and Chief of Staff of the President’s Council of Economic Advisers, and is the author of “Raising an Entrepreneur: How to Help Your Children Achieve Their Dreams.” Follow her on Instagram @margotbisnow.

Don't miss:

• I raised 2 successful CEOs and a doctor. Here's the 'unpopular' parenting rule I always used on my kids
• Child psychologist: The No. 1 skill that sets mentally strong kids apart from 'those who give up easily'
• I talked to 70 parents of highly successful adults—here are 4 phrases they never said to their kids

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