Answer: Brachyscome (swan river daisy), Helipterum (everlastings), Helichrysum (strawflowers), and Trachymene coerulea (blue lace flower) are all flowers native to Australia. You could also grow New Zealand spinach, if that's appropriate.
As far as an ABC garden, let me know what letters you are missing, and I can try to help you out. (Maybe we can "cheat" a little and use the botanical name!)
Also, have you checked out the National Gardening Association's Web site? (www.garden.org) Click on the "Kids and Gardening" section for lots of great ideas for gardening with children.
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