Common Core Standards: Math
Some relationships function just fine and others really, really don't. Your grandparents who just celebrated their 50th anniversary? Functional relationship. That love affair you have going on with that carton of mocha almond fudge in your freezer? Dysfunctional (but oh-so delicious) relationship.
In satisfying these standards, students will learn how to think about, compare, and apply functions to real-world situations. Probably won't help much with their personal relationships, but hey, it's better than nothing.