Welcome to AA, Worthincrew!!
With a small peaceful tank, go for 1 inch of adult fish per inch. Aside from the more colorful tetras, such as Serpae, have you looked at white clouds (I think they are called white cloud minnows). Of the tetras, cardinals and silver tips are nice, as are black neons and regular neons. You may find that regular neons are not as hardy as the other fish. If the tetra or whatever you choose grows to be an 1"-1 1/2', put in a school of 5 to start with.
I would use cory cats on the bottom because they are so cute--3 three of them.
Others will have different suggestions.
Read up on the nitrogen cycle in the Articles section. Using the fishless cycling method is better than cycling with fish, but will take the fun out of presenting the tank to your daughter. If you know someone with an established tank--it's best to get some bacteria from their filter and add your daughter's fish right away.
I hope this makes sense--I must run (must get to a neuroscience conference
*edit: Here's a link that discusses cycling with straight ammonia.