This takes two children - wait until Mum absolutely cannot leap up and stop you, then the toddler does a poo in the potty and the crawling baby immediately grabs it and plays with it.
Tidy up your bedroom by putting every item of clothing from the floor into the wash without checking it, so that the clean, ironed, folded clothes Mum gave you last week and that you dumped on the floor instead of putting away, go back into the wash again.
Bring your friends home and have a water fight while you are all still in your school uniforms, so that your mum not only has to get your uniform clean and dry for the next day's school, but also has to apologise to your friends' mums.
This one particularly winds dh up - tell Dad that your phone is out of credit not when he is at the pc and can top it up for you, but when you are in the car on the way to somewhere where you will need to have your phone.
See - I told you I could go on....