Can you keep a tidy house without nagging?

[Ohdoleavemealone]

My kids are 6 & 8. Too young to independently remember to do stuff and need reminding but they are so messy that I feel like I am constantly nagging.

My 6 year old gets everything out all the time. When she eats she transfers things from packet to random object (like a toy cup or a packet lid) often spilling things everywhere.
My 8 yr old just dumps his shit where he lands. Removes clothes and leaves them on the floor. Finishes breakfast and leaves the bowl there. Finishes with a book and leaves it on the floor.
Is this nagging necessary? Is it their age or do I just need to be firmer?

I always expected meal times to be almost manageable. Getting dressed is likely to be a pain in the ass for quite a while. That said, yes I think it's good to try to instil some sort of ideas about keeping clothes in the right place. I'd have a bit of a go on the clothes front. Life really is too short to get stressed over the food part when they're still relatively young. If it's any consolation my daughter, now 18, is way tidier than I am. No idea how it got that way but she honestly is great with keeping her clothes and other stuff tidy. Hang in there !