The Chinese Elm, Ulmus Parvifolia is great beginner bonsai tree.  They are found naturally in China, Japan, Korea and Taiwan and usually srop their leaves in the winter, But not always.  With enough light and warmth, the Chinese Elm is evergreen.  Another interesting thing about the Chinese Elm is that it’s one of the few trees that can easily be grown indoors or out.  While I personally prefer to grown everything that I can outside, the Chinese Elm can make a great semi evergreen or evergreen indoor bonsai.
If you do decide to grow them outside, give them lots of protection in colder climates – zone 5 and 6. You can also leave them outside in the summer and in the winter bring them indoors to a cool ( not western exposure) windowstill or a glassed in porch.
One thing you should know about your Chinese Elm is that even if it holds all its leaves, it will need a winter rest and so when the days are shorter and the weather is cooler, ease off on the water and the fertilizer (fertilize once a month instead of every other week) and expect that you’re going to have at least some leaves yellow and drop. In fact, you can expect that they will probably also have some black spots on them before they drop.  Not to worry, but if the leaves turn brown and shrivel up before they fall you’re underwatering. Remember not to let your Bonsai become bone dry.  That is never a good thing.