What are some good beginner schooling fish?

Guppies are not schooling fish.

I'd recommend Black Phantom Tetra and Harlequin Rasboras.

They are both cool looking and active schooling fish, and they are both hardy!

Gary's suggestions are good.

I will add another one, White Cloud Minnows.

They are small (great for smaller tanks), don't need a heater (but can live at lower tropical temps) and are quite hardy. They may breed in your tank, but they don't over populate like guppies do.

If your friend is over run with guppies, ask them for a few males. Then you don't have the breeding problems. You can keep Guppies and White Clouds together, just set the temp to about 22C and both will be fine.

Ian

Neon tetras, glofish, zebra danios and glow tetras are all great beginner fish. They are very hardy and peaceful. You could have a school of 5-6 of each of these if your tank is big enough and they would all get along great and it would be a very pretty tank.

You could also get some Cory cats or loaches as bottom feeders. They are also peaceful and will give some activity on the bottom of the tank

Don't forget - if you haven't done this or planned this already - you'll have to have a filter, heater, substrate vacuum (for cleaning out the solid fish waste) aerator and air pump (so an air stone or bubble wand to put oxygen in the tank). You'll have to 'cycle' the tank first - it's best done without fish in it as the unstable water parametres during the cycle are likely to kill them.

If you are going for small and peaceful community fish, the minimum size tank you want is a 15 gallon. Community fish such as tetras, rasboras, danios, various species of Corydoras catfish all need to be in groups of 6-8 so you want a tank large enough to give them plenty of space to move and enough places for them to hide or claim as territory (in the case of some species of Tetra like the Black Phantoms). I would recommend those I've just mentioned but choose ones that grow to no bigger than 2 inches if you're getting a 15 gallon (roughly 55 litre tank).

Generally fish won't breed unless the tank meets their spawning requirements, some need a low pH, some need soft water, some need low temperatures etc. so if you don't want fish that breed like crazy, consider ones that are difficult to breed or have breeding requirements that your tank won't meet.

For learning about the nitrogen cycle (which every beginner needs to know about to keep healthy, long living fish): http://www.aquariumadvice.com/forums/f15/the-almos...

For information on the different fish species available and their requirements: http://fishkeeper.co.uk/site/databank

A small bit of information about water hardness in case you need it: http://www.tropical-fish-success.com/aquarium-wate...

Guppies aren't exactly schooling fish, although they sort of school loosely.

Some good beginner schooling fish:

zebra danios

giant danios

tiger barbs (but they sometimes nip fins)

black skirt tetras

hatchet fish (keep tank covered)

Silver dollars (if you have a tank of 50 gallons or more)

Edit: Yes! White Cloud Mountain Minnows. I meant to mention them, but I forgot. Thanks, Ian.

Tetras! They come in all different shapes and sizes they all do well together if you get like a group of 5 for one kind of tetras, then add a school of another kind

I also have to agree with tetras. They are very active and very friendly.

I absolutely LOVE neon tetras if you haven't heard of them (look them up) and get some of those!