My daughter (now 11) went through that when she was 10, only she was using the full water level to wash a pair of shorts & a tee shirt. She also used too much detergent, thinking it would make her clothes cleaner.

Could you use his interest to actually show him how to do laundry correctly - sorting, water temperature & level, folding? He's going to need to know how to do that at some point.

If he's only visiting occasionally, and not actually living with you, I'd be tempted to throw the breaker switch while he's there (and hide the detergent)--that way he CAN'T use them. Sometimes it's easier just to prevent a problem that to educate around it--especially when it's not a child you're responsible for.

Good luck.

A child of 10 years is old enough to follow orders, if he is told to leave the laundry equipment alone, then he should leave it alone.

Tell him flat, that in your house, he must follow your rules and messing around with appliances is strickly against the rules.

I certainly wasn't advocating NOT teaching him right from wrong. Just suggesting that at the cost of major appliances these days (just bought a new washer and dryer myself), it might be prudent to also fix it so he couldn't use them, just in case he wasn't in the mood to listen to Grandma's rules--kids that age don't always feel they have to pay attention to anyone who isn't their parent.

my son just washed a banana in the washing machine
what a mess

Lock it up, unplug it, you can keep him from being able to use the machines and/or the soap.

The thing is, if you want a next step beyond letting him know the rules... the next step is to respond to the apparent fact that he cannot or will not (can't tell) do what you want. You can keep him from being able to use the soap or machines by locking one or both away and/or interfering with the power supply and/or figuring out to mechanically lock the washer so nothing can go in. One more, the water supply can also be stopped.

An intermediate sort of step would involve making a list of household rules. Make a couple or a few copies of a list of 3-5 rules (short but sweet ones that you decide upon). Post one in a central place like on the refrigerator, and one copy on any relevant objects (like one right on the washer), and send a copy with him so he can have his own reference.

Additionally, or instead if you will let him use the washer on occasion, print up big step by step instructions... Soap measurement is tricky because it seems, intuitively like more is better, or will clean more. Adults fall for that too, not just 10 year olds so it's not unusual. You can explain how it is bad for the fabric, or how too much interferes with rinsing so the clothes don't in fact get cleaner. On the instructions though, have a dedicated measuring device and state how many scoops or whatever.

People, even 10 year olds have their own thoughts and feelings and motivations and everything else that makes them human. You can tell him, and you can feel like he heard you and paid attention and has a good enough working memory to always then know... and like he should have the kind of internal braking system where even if he _wanted_ to do laundry he would stop himself simply because he would remember what he was told. Lots of different things can interfere with his 'getting' any of those steps. (At the same time you feel like you told him, he's thinking about how cool it is to be at his grandmother's house and who knows what all other 10 year old boy thoughts. Maybe he hears, but his attention is on something else. Maybe he hears and remembers but his parents are working on getting him to clean up more so he sort of has a 'prior directive' to clean up after himself... basically his primary caregivers may be training him to use washers automatically and that will interfere if you want him to do something else or think something else.)

I don't know if he does think they are toys. Maybe he thinks he's helping or he wants to feel 'grown up' or who knows... I do know that you can probably communicate better with him about this is you focus on what you want rather than what you don't want. It's also good to not even address what his possible (apparent?) thoughts or motives are because that will distract you both from the matter of wanted behavior. (People tend to react as if they were being attacked, or personally insulted when others presume to know what they are thinking or why they do what they do, even 10 year olds.)

P.S. You can talk to his mother directly about what she allows or doesn't allow. And, if he does do laundry at home and does it well you can also find out what worked in that situation (he might be applying his same process from home to your machine and your soap and not realize that there can be important differences).

this looks like a fake post to me ... like the one with the plant-eating.

jmho, maybe I am wrong :>)

I agree. It's the same style as all the others.

Fake or not, it's something to think about. A 10-year-old kid might see this as a sign of independence or something...I used to wash my clothes at about this age because my mother would periodically do things like put sweaters in the dryer....etc. etc.

I just recently saw a show on TLC about limb replacement...a 3-year-old had gotten his arm ripped off in the spin cycle. Not pretty.