When children first learn to speak, it’s precious. Soon, you can’t shut them up. When they first hop on your computer, pecking at the keyboard and scooting the cursor around with the mouse or trackpad, you exclaim, “They’re so smart!” But after weeks of them hogging your work-issued laptop to print Pokémon coloring pages or Google cats, you wonder if it’s time for a family computer.  That’s the story in my house, and a variation on the theme that emerged when I spoke to families and educators around the country. My virtual focus group of 50 parents—all with children of elementary- or middle-school age—proved that the family computer is alive and well. For this crowd, price, durability, safety and battery life were top priorities. But navigating so many new choices can be a challenge.  I set out asking a simple question: At what age should children get their own computer?  In first or second grade, children start regularly using computers in school. It makes sense for children that age to have access to a computer for learning games and other safe activities. But it shouldn’t belong to your child—it’s a family resource that requires supervision. Even if you’re not worried about them searching for trouble, parents know that even the most saintly YouTube clip can have related videos of a more devilish nature.  “Hold off on an individual computer as long as you can,” says Garrett Fogel, a first-grade teacher at Green Elementary School in my town of Dublin, Calif., who has taught nearly every grade from first through eighth and has two boys of his own. “The family computer is usually in a room where parents can monitor it. That’s best for smaller kids,” he says.  By fourth grade, many students are doing quite a bit of computer work at school, and it snowballs from there.  “High school is where it becomes more of an issue,” says James Steyer, chief executive of Common Sense Media, a nonprofit advocacy group that promotes safe uses of technology for children and families. “You can see why they want access to their own computer because of the homework factor. But they’re also playing games, so you want to find the balance.”  The traditional family PC was a desktop system, permanently fixed in a central location. It’s never been a more cost-effective option. There are towers for $400 to $600 that you can pair with a monitor. As you climb up above $1,000, you also have some slicker all-in-one options, such as an iMac or one of HP HPQ 1.57 % ’s Envy touch-screen PCs.  Despite the supervisory advantages of a desktop, however, I found that parents increasingly are interested in a computer they can put away. The Windows world has more affordable laptops than Apple’s popular MacBooks. Dell’s Inspiron 11 3000 Series—configured with a touch screen, a Core i3 chip and 128GB of solid-state storage—costs $600. It’s a nicer, sturdier pick than Microsoft MSFT 1.90 % ’s own heavily marketed Surface tablet, which starts at $500 without the $130 keyboard.  Beware anything below that price and avoid anything without an Intel INTC 1.14 % Core processor: Truly cheap Windows laptops will leave you frustrated. Even on Microsoft’s own new Windows 10 Edge browser, pages are painfully slow to load.  MacBooks, which sell new at $900 or more, most often came up as ideal hand-me-downs. That shiny laptop you bought five years ago may have lost its luster, but most children won’t notice.  If you are going to hand over an old Mac or Windows PC, make sure its software is up-to-date. Parental controls are better on the most recent operating systems. So are safety measures that protect computers from phishing and other threats that could afflict children and adults alike. Free software called CloudReady can also help turbocharge a computer that’s past its prime.  In some cases, a hand-me-down could benefit from a RAM memory upgrade or a new storage drive. If you swap in a solid-state drive, you could cut your old computer’s boot time in half and speed up a lot of other interactions, too. Worst-case scenario: You have to take the computer in for a new battery.  A trickier question: Does the iPad, which may have been a part of a child’s life from a far earlier age, count as a computer? The answer is yes, but given its price it may well not be the one best suited to your needs.  Parents and teachers of younger children like iPads because they’re so intuitive to use. Their processing power has, in recent years, become vast. And if a child has to lug a computer around, there’s no lighter option.  The combination of Web browser and app store ensures that children can do most or all of the activities they can do on any other computer, and a bunch of things they can’t do with other devices, such as shoot and edit a movie. Apple’s new iPad Pro models even support a pen that’s great for visual arts.  The catch is that all of this comes at a significant cost: A 32GB iPad Pro with keyboard case costs about $750. A cheaper alternative—the iPad Air 2 with a Logitech LOGI -0.33 % keyboard case—comes in around $500, but that’s before you pay $100 to bump the unforgivably paltry 16GB of internal storage up to 64GB. And in both scenarios, the screen is just 9.7 inches, and the keyboards aren't very good. (The 12.9-inch iPad Pro with keyboard case costs nearly $1,000.)  Kara Larcome, a mother of two and the science, technology, engineering and math curriculum coordinator for North Andover Public Schools in Massachusetts, says that, as she prepares to buy a first family computer, she’s leaning in another direction.  Her children are comfortable around iPads, but she wants her 5-year-old to learn to use a trackpad, and to type on a physical keyboard. Since she and her husband already have computers, an inexpensive Chromebook—which runs Google’s Chrome OS and is designed almost entirely around Web browsing—is the most justifiable purchase.  One reason Chromebooks have taken off is that many schools are choosing Web-based workbooks and reading modules, say the educators I spoke with.  When using Chromebooks with children, you create supervised accounts and monitor what children do online via a dashboard. You can also ban sites by name, or list only the sites you want your child to visit. The tool is rudimentary—there’s no switch to flip that automatically eliminates the nastiest of the Web, for instance—but it can be handy.  A new Acer ACEIY 0.00 % Chromebook 14, with a 14-inch screen and, according to its maker, 12 hours of battery life, is made with sturdy, lightweight aluminum and packs enough power for smooth Web work. It sells for $300.  A Chromebook still can’t run some very common software. Minecraft, the insanely popular construction-and-adventure game, is now also a classroom tool. Chromebook’s inability to access it came up as a deal breaker for several families I spoke to.  But Ms. Larcome, who has a work-issued MacBook Air, says even she would use a Chromebook at home. “None of the features I would need are missing.”  She’ll have to be careful, though. If she starts using it too much, her daughter may have to ask her to kindly find her own computer.  Write to Wilson Rothman at Wilson.Rothman@wsj.com or on Twitter @wjrothman
When should children get a computer? Mac or PC? Chromebook or iPad? Wilson Rothman has what to know when facing the milestone.