I'm here to play devil's advocate and suggest a slightly different take: my parents really never talked about money at all, and it worked really really well. I see elements of this strategy in some of the answers above.
I didn't get an allowance, wasn't ever told I needed to get a job, never babysat or mowed lawns, my parents didn't use explanatory phrases like "can't afford it" or "that's not a priority," and I absolutely never heard words like "rich" and "poor." And yet, I never really asked for much as a kid, didn't really want for much at all, didn't worry about money ever, didn't want the homes or toys of my occasional much-richer friends, and when I hit 16, I woke up one day and told my parents "I need to go out and get a job!!" and I did just that.
Sometimes it's helpful for kids to not have anything about their relationship with you, or your relationship with others, seem trasactional. Instead, model how you want them to behave and they'll follow. (Also, keeping good company for yourselves and your kids as others have suggested is great, too...because they'll mimic their friends, not just you.)
My parents are extremely generous people. As a child and young adult, I saw them give to the church, give to charity, give to our friends, and provide endless hospitality to others. I saw my dad leave home and work hard every day and come back tired but happy, ready to ask all about my day. I ended up wanting to be like them, and I learned wordlessly early on that it's much more fun to give and work than to receive and be lazy. When I got older, I realized that I grew up in a solidly middle-class family and that I usually had little luxuries at my disposal that other kids didn't. But the desire to be generous to others remained, which is what eventually made me end up here, practicing frugality over little personal luxuries so that I can be generous to others.
Just a few thoughts. I think any good parenting strategy about money is going to involve a custom balance of being open with many things while concealing some things that are beyond a child's understanding. But my biggest recommendation is this: let your children have a childhood. They have the rest of their lives to think about money and work. Right now, they have the joy of getting to rest assured in your (modest to their eyes) provision.