It's never too late to try something new. Rather than flipping through your kids' Spanish flashcards after they go to sleep, commit to learning a new language as a family. It doesn't matter if it's related to your own culture or one you can hardly spell—as your skills develop, such an experience will provide even more opportunities to practice together.
If the time is right, start a fund for a family vacation to the country where people speak the language you're studying. There's no better way to learn than through immersion.