The first is the humble list. Lists really are so useful. This one is for the big kids to follow every morning. The idea is that the TV or computer does not go on until they have done everything on their list.
The second is a version of the zip-lock bag. (My mum and I go nuts for zip-lock bags, in all sizes.) At the beginning of every year I buy each child an A3 size plastic zip folder and everything paper that arrives in the house goes into it.
Certificates, awards, artwork, schoolwork, birthday cards etc....
At the end of the year you can cull it down a bit and only keep what is really precious, and when they leave home I will be handing them a large pile of plastic folders.