The Problem with Kids and Keys
Children lose things. This isn't a character flaw — it's a developmental reality. Executive function (the mental skill that helps you keep track of objects) doesn't fully mature until the late teens. Expecting a 7-year-old to reliably manage a house key is like expecting them to reliably manage their homework — it works sometimes, but the failure rate is high.
The costs add up. Each lost key means a potential locksmith call (€80–€150) or at minimum a new key copy (€5–€15 for standard, €30–€60 for SKG-certified). If the key was on a ring with identifying information, you may need to change the cylinder entirely (€50–€120). Over a childhood, this adds up to hundreds of euros.
There's also the safety dimension. A child standing outside a locked house is vulnerable — especially in cold weather, rain, or after dark. And a lost key in the wrong hands could mean someone else has access to your home.
Options by Age
The right solution depends on the child's age and maturity:
Young children (6–10): At this age, kids lose everything. A physical key on a lanyard around their neck works but is uncomfortable and visible (security concern). A better option is a Nuki Fob — a small, durable keychain tag that unlocks the door with a tap. Attach it to their school bag strap where it can't fall out. If lost, deactivate it instantly from the app and activate a new one. Cost: about €30.
Older children (10–14): PIN codes are the sweet spot for this age. Kids this age can remember a 6-digit code but still lose physical objects regularly. Set up a PIN on the Keypad that only they know. Bonus: it makes them feel grown-up and responsible. If they share the code with friends (and they will), change it in the app — 10 seconds.
Teenagers (14+): Most teens have phones, so app-based access works. Add them to the Nuki app with their own account. They can use Auto Unlock (door opens as they approach), manual app unlock, or a PIN as backup. You can see when they arrive home in the activity log — useful for peace of mind without being invasive.
Activity Log — Peace of Mind for Parents
This is the feature that parents love most: the activity log shows you exactly when your child arrived home. No more calling or texting "are you home yet?" — you get a push notification the moment the door is unlocked.
For younger children, this provides genuine safety monitoring. You know they made it home from school, you know what time they arrived, and you know the door locked behind them (if Auto Lock is enabled). For a working parent, this replaces the after-school phone call with silent, automatic confirmation.
For teenagers, the log provides oversight without micromanagement. You're not tracking their phone or reading their messages — you just know when they came home. Most teens actually prefer this to the alternative of check-in texts, because it doesn't require them to do anything.
The log also shows if the door was opened at unusual times — useful for knowing if your child is sneaking out at night or if someone unexpected came by.
Sharing a Code vs Sharing a Key
When your child shares access with a friend ("Come over after school, the code is 123456"), the consequences are very different from sharing a physical key.
If a friend knows the code: you see it in the activity log ("Guest code used at 15:42"), and you can change the code in 10 seconds from anywhere. The friend never had physical access to copy — they just knew a number that you can change.
If a friend has a key copy: you have no visibility into when it was used, no way to revoke it remotely, and the friend could make additional copies. Getting the key back requires physically collecting it, and you're never 100% sure they didn't copy it first.
With a smart lock, "sharing access" is a temporary, trackable, revocable event. With physical keys, it's a permanent, invisible, uncontrollable transfer. For families with children, this difference is enormous.
Setting Up Nuki for Your Kids
Here's a step-by-step for each option:
Nuki Fob (ages 6–10): Pair the Fob in the Nuki app (takes 30 seconds). Attach it to your child's school bag with a sturdy clip or carabiner. The child taps the Fob against the lock or Keypad to unlock. If lost, deactivate in the app immediately.
PIN Code (ages 10–14): In the Nuki app, go to the Keypad section and create a new user with a 6-digit code. Give your child a code that's easy for them to remember but not obvious (not 123456 or their birthday). You can set time restrictions — for example, the code only works between 12:00 and 19:00 on school days.
App Access (ages 14+): Invite your teenager through the Nuki app using their email. They download the app and get their own access. You can enable Auto Unlock for them so the door opens automatically when they come home. Their access appears in the shared activity log.
For all options, make sure Auto Lock is enabled so the door locks behind them. Kids are notoriously bad at remembering to lock the door, and Auto Lock solves this automatically.