Slightly different tone of thought provokers today... Like many others, a second or third reading later might reveal multiple interpretations.
1. I'm made of rubber, you're made of glue,
everything you say bounces off me and sticks to you.
2. You must get good at one of two things - planting in the spring or begging in the fall.
3. Ninety percent of everything is crap.
The first quote sounds like the prattle of a primary school kid but it can be employed as a way to deal with what we hear. It can also be seen as a truth about what we say to others, whether positive or negative.
The third sounds like a wisecrack but it again is a useful thing to remember especially in today's hyper-competitive environment when everyone is trying to cope with new concepts, gadgets, information...