Congratulations on becoming a member, Singin_Angel!
Our congregation went through a period of wonderful growth that is just now starting to level off a little, but our situation seems like it is different from yours in pretty much every way.
We are the only UU church in our metropolitan area. We have a building that we have been in for more than 50 years. What I would suggest for you would be looking through the past Breakthrough Congregations and finding one (or more) that has similarities in size and situation with your congregation and watching its Breakthrough video. You can find the 2009 Breakthrough Congregations along with other articles about encouraging growth on this UUA web page: Growing Congregations
My congregation cycles through some favorite RE curriculae for the various age groups and also tries a few new things each year. This year my dd is in the 4th grade. She is doing The New You the Creator during first service. She absolutely adores this class and I think it is wonderful, but I must mention that dd once said to me, "That's not Religious Education. That's just art class"
During second service she did Bibleodeon in the Fall. This class teaches the kids about well-know Bible stories using activities and lots of dramatization (skits). DD also loved this class and I heartily recommend it as well. Now during second service my DD is doing Philosophers Club. Based on talking to her this sounds like a very good, challenging and thought-provoking class. It sometimes produces anxiety in my dd, but she is pretty sensitive to thought problems like "What if you are stranded on a Desert Island?" or "What makes you different from a machine? How do you know you are not a machine?"
Last year my daughter did Experiences with the Web of Life
, a heavily nature-based class that gets a big thumbs up from both of us. She also did Moral Tales
, one of the Tapestry of Faith curriculae and honestly, this has been my least favorite of all her RE classes at my church. The approach seems excessively preachy and behaviorist to me.
In first grade my dd took Free to Believe. I think this is an excellent curriculum for young children because it helps them develop a sense of identity as Unitarian Universalists. My dd did not take any of the RE offerings for younger children so I can't offer an opinion on them, or on the classes for older kids that she has not gotten to yet. I have heard great things from others about Our Whole Lives and our new Coming of Age program. You can read brief descriptions of all the current children's RE offerings at my church here