I thought of the song lyric 'Tea, a drink with JAM and BREAD...' and I think BREAD could play in with the 'bread of life' symbolism.
Be Really Excited About Diocese
Diocese is not the sort of word 6-12 year olds would be likely to use, but I can't think of any better ones right now. As Tony said, it depends on what kind of church it is. It may be that a D word leaps out at you immediately because you know more about the situation. I think, 'Be Really Excited About...' is a good start though, as I hope that's what you want them to be.
If the adults get together for refreshments after mass, you could even call that group TEA... The Ecclesiastical/Exalted/Excited/Exhausted (though they're probably not exhausted if you take the kids of their hands!) Adults. I'm short on time and inspiration at the moment.