The parents will eat both the eggs and the tadpoles. You need to put the eggs/tadpoles in a separate tank with an airstone. Algae tablets for fish are the best food I've come across for any species of tadpoles.
If some of them make it to being frogs, keep in mind that an adult can and usually will eat any noticiably smaller frogs. On a side note, I've often noticed that you can tell the potential gender of eggs and tadpoles just by looking-the larger ones are female. There's also a slight color difference but it's been a few years and I can't remember which are lighter but the size is usually a pretty accurate way to tell them apart if they are from the same egg mass.
Used to have a 15+ year old pair of african clawed frogs that would lay eggs every time the tank was cleaned. A 15yo female is about 10" long...males are a slightly less than half that.