The Giant African Bulfrog (Pyxicephalus adspersus) made #3 on Animal Planet's Top 10 Animal Dads! Like some of our local frog species, the Giant African Bulfrog lays eggs in temporary ponds - but after the eggs are laid, male frogs remain in the ponds to protect the eggs and tadpoles.
This BBC video show the bulfrog dad protecting tadpoles from predators and desiccation:
In addition to the Giant African Bulfrog, some other amphibians provide parental care for eggs and tadpoles. For example, male midwife toads (genus Alytes) carry fertilized eggs on their backs until they are ready to hatch. A good summary of parental care in anurans (frogs and toads) can be found here.
In case you are wondering, none of the anurans that breed in Duluth exhibit parental care. However, female Eastern red-backed salamanders (Plethodon cinereus) guard their eggs until they hatch. More information about this entirely terrestrial salamander can be found at the University of Michigan Museum of Zoology's Animal Diversity Web.