Wikipedia is a great resourse for dads of curious kids. My kid asks a lot of questions and he is interested in a lot of fronteer stuff  like  aero gels, plasma, fusion and space. In the past times you would just buy books for that but well… It is not good any more because it takes years for them to be updated while things change much faster these days. Many books will still call Pluto the planet or will not have enough info about recent advances in nuclear physics. Wikipedia allows access to all this information in the real time changing how we can learn. Of course  Wikipedia is not along there are a lot of other resources in the Internet providing amount of information we could only dream about only 10-15 years ago but Wikipedia is surely the great place to start research about virtually any topic.