A survey for a publisher suggests parents' general knowledge is not much greater than the average 11-year-old's.
Simon Cowell is said to be more familiar generally than the Queen or Prime Minister Gordon Brown.
Barely half of parents told Dorling Kindersley Eyewitness Guides they thought they were smarter than their children.
In some subjects in a quiz taken by more than 1,500 parents and children aged eight to 12, the youngsters did actually know more.
The research was done to publicise a new series of guides, but it highlights issues about how much parents can help with their children's homework.
It included a survey of parents, which suggested many felt they simply lacked the knowledge to answer many of their children's endless questions - such as how far away is the sun, how deep is the ocean, how do birds know which nest is theirs?
Parental involvement is known to be a crucial factor in how well children do at school.
That is something the BBC is hoping to address with a new website onto which parents can upload video clips of tips for others.
It is called Backpage, and will be running over the next four months under the slogan "by parents, for parents".
"It's true that parents swapping advice won't be everyone's experience, but what we want to get across is that some parents do swap tips with each other and for parents who may be struggling, the new site is a place they can get the answers they need," said producer Jon Aird.
One of the aims is to sift through the camera or mobile phone videos to spot potential new presenters.