The traditional past time when this occurred was a full course of daytime TV, but with the explosion of the internet I think that's all a thing of the past. Puzzling over bookmarks, the parents may choose a webpage for practicing Spanish or perhaps a website reviewing the history of the Roman Empire. Learning on the internet is fun because there is so much out there and in so many different ways. Kids can talk to others working on the same subjects. The participants, which may include lurking teachers or other experienced people willing to assist, are keen to help explain and to discuss their own adventures with any problem someone brings to the virtual table.
Websites are where the magic of internet education becomes obvious.
These sites are not long, dry, text files, they are often truly interactive and with a little parental assistance can be used by a wide range of ages and grades. It's best described as a learning feast where the buffet table is endless and you're always craning your neck to see what that good smell is coming from the next link. Some people argue that the internet will do the work for kids, causing them to become lazy. There are calculators to do your math for you and well-written articles from which text could be copied verbatim for papers. Obviously, whatever is already done to prevent children from relying too heavily on such things should be kept up.