My guesses as to your intentions, based on the general nature of the request, are either turning off wireless access while you're at work, and so nobody's supposed to be home and using those devices, or restricting kids' wireless use on gaming consoles/tablets/smartphones during homework time and after bedtime. I will assume, for this answer, the latter situation, because it's the more feasible from my perspective (if someone's in your house using your devices without your permission while you're not there, I posit you may have much bigger security problems).
There's nothing you can do with your router to prevent your kids getting access to someone else's. Not legally, anyway; the best you could do is to jam the channels used by nearby routers, but not only is that a violation of FCC regs, but the routers you're trying to jam will see that jamming noise as interference and switch to an open channel. So unless you're using your equipment to emit a broad-spectrum noise across the entire 2.4GHz band, which is extremely illegal despite the "open" nature of this spectrum, your router can't help you keep your kids off your neighbors' routers.
However, your neighbors can help you keep your kids out of their WLANs. Simply go around to all your neighbors with Wi-Fi hotspots that are visible from inside your house (your own cell phone is your best tool for seeing which house has what network), and ask if they can help you out by securing their WLANs. They should be happy to help; very few homeowners want someone they don't know about piggybacking on their Internet connection, draining bandwidth and possibly doing things that could come back to haunt them. WPA2-PSK wireless authentication/encryption, WPS disabled if available on the WAP, SSID broadcasting turned off, and MAC whitelisting of approved devices (or at least blacklisting of your kids' devices; this will require more maintenance on everyone's part as your kids get new or replacement devices) will provide a decent level of frustration for unauthorized users including your kids.
If one or more of your neighbors simply will not help you keep your kids off their WLAN when they're not supposed to be connected, then there's a second option, which is to configure your kids' devices to prevent them being able to connect to any non-remembered WLAN. As stated in other answers, you basically lock this down with permissions and an administrative account on the device, which your kids will not have access to. This isn't always possible, and it's never easy. With Windows PCs, you'd basically use Group Policy to prevent non-administrative users from connecting to a non-remembered network. Not all Windows versions have this; basically you'd be required to buy the "Professional" or "Business" level of the software, which has all the doodads needed to be an Active Directory client (allowing remote administration, domain logins, etc). Smartphone/tablet OSes like Android/iOS, AFAIK, do not have this ability "out of the box"; the intent of the OS design is to allow WiFi use wherever it may be obtained, to avoid using the cell data plan (and that data plan, if it exists, can still be used even if you prevent all unauthorized WiFi use, unless your provider allows you to turn data access on or off for various devices from a central control panel, like your own smartphone). You may be able to install a "childblocker" app that restricts use of the data plan or certain apps during various times or on command from your phone.
However, there's an even easier solution to the whole problem, which probably should be the first option; confiscate your kids' devices during the times you don't want them used. Simple, effective, free. If they're supposed to be doing homework, then any entertainment consoles that use the Wi-Fi (XBox, PS, Wii, Blu-Ray, Apple TV, Google TV, SmartTV) are turned off, and your kids are in a room that doesn't have them while they are doing their homework. Their tablets and smartphones are in your hands, or a basket next to the entertainment center with all the banned console devices, and if they need their laptops to do their homework (Wikipedia is a legitimate use for Internet during homework hours) then you have monitoring software on said laptops keeping you apprised of what they're actually connected to, or you can simply whitelist websites from the control software. Some may call this draconian and oppressive; I call it tough love and good parenting.