I have lavender - I love it! I have it planted all around in different flower beds, getting all types of sun exposure (from full sun to little sun). I pick it often when it's growing which promotes new growth, and allows me to make good use of it indoors (in vases with other flowers, dried flowers, in the bath tub!...even makes a nice "bow" for gifts wrapped in brown paper and twine). I haven't had any problem keeping it growing. As mentioned above, feel free to neglect it - it should do just fine with no special care.
Kids are great for helping in the garden! Get them a little wheel barrel and they'll move anything you ask them too! Pint size shovels, hoes, and rakes (real ones, not plastic) are inexpensive (few bucks a piece) and really get them motivated and make them feel like pros! We put out a very large veggie garden (enough to eat fresh, store for winter, and share with friends) and grow a lot of different things. And I stick flowers wherever I can on the three acres here - even in the woods!