“Mom, what’s a tuppence?”

My 8-year-old son and I were curled up on the couch watching what might be my favorite film of all time. “Two pennies,” I said. “It’s British money from a long time ago.” I was quite happy about the question, honestly. Happy to celebrate any excuse to turn family movie night into a teachable moment.

“What would that be worth in today’s money?” he asked. I had no idea. So we googled it.*

Mary Poppins was released in 1964 and set in 1910. But as we looked for answers about the dated form of currency referenced in the film, I realized something I hadn’t before: Unlike the now-defunct tuppence, the advice Mary Poppins dispenses is as solid as ever.

In fact, the more I considered it the more I found her words were stunningly well-suited for the digital age.

“Enough is as good as a feast”

This is something we don’t hear—or repeat to our children—often enough these days. When obesity is a bigger killer than hunger, our landfills are overflowing, and friends are available via text or chat around the clock, this truism should be our collective mantra.

Having just the right amount of food, just the right amount of space, just the right amount of stuff is something we should emphasize. And not just because restraint feels admirable. There are some real personal benefits to be had from seeking just enough. I’ve seen genuine anxiety arise from having too many things to manage, too many options. Psychologist Barry Schwartz wrote a whole book about it (The Paradox of Choice—Why More Is Less). But it requires a level of discipline that at times feels superhuman to resist the urge to take as much as we can.

An obvious extension is our penchant for being constantly connected. Teens check their phones relentlessly (sometimes 100 times a day) and spend up to nine hours a day consuming media. Flexing their self-control muscles isn't something most teens will do on their own. They need reminders. They need parents to show them how it's done.

So the next time you’re watching Mary Poppins with your own kids, consider pausing it long enough to explain to them how “enough is as good as a feast.”

“Well begun is half-done.”

The sheer simplicity of this statement should make it a more often used gem. If you can get off on the right foot, well, you're already halfway to the finish line.

The applications for this are broad and it’s useful in almost every parenting setting—particularly when it comes to tech and social media. For me, this means the rules you put in place for the oldest child in your family will be assumed by all subsequent children to be “The Rules” (whether you thought about it that way or not).

The truth is, it’s much harder to make course corrections than it is to start with a well-thought out plan from the beginning. This goes equally for cell phone rules, social media acceptable use, and household chores. This was already my favorite piece of parenting wisdom, even before I remembered that it came from my favorite British nanny. And, to be fair, Mary Poppins isn't the only British nanny to offer up this advice; Traci Hogg, the Baby Whisperer, offers the same rule, put another way: “Start as you mean to go on.” Put in the effort required to get things off to a good start, and you’ll spare yourself a whole lot of whining later on.

“That’s a pie crust promise. Easily made, easily broken.”

So many things today are disposable. Promises made to each other shouldn’t be among them. Social media contributes to this problem by making relationships both easier to form and easier to sabotage. It’s important to remind teens that promises made to friends should be deliberate and durable.

There’s also something to be said for encouraging teens to spend time together in person. It’s certainly harder to have difficult conversations face-to-face (which likely contributes to the prevalence of break-ups via text), but there are lessons about the human heart you can only learn by looking in someone’s eyes. Encouraging teens to make time for their friends—actual face-time, rather than FaceTime—may make them less likely to make those flaky promises.

"Close your mouth, please, Michael. We are not a codfish."

This is not so much a piece of advice as it is a brilliant distraction. Go on—say it to your kid the next time they’re in the middle of arguing with you. It might not teach them a valuable lesson, but I’ll bet it buys you a minute of silence. (Bonus points if you can do it with a passable British accent.)

For all her fairyland charm, Mary Poppins seems to be a pragmatist. And her practically perfect advice on the art of childrearing not only stands the test of time, I think it actually improves with age.

Want to know what a tuppence is worth today? Look here. (There's a Mary Poppins reference toward the bottom that's worth the scroll.)