Ruby on Rails: Models without matching database tables

I’ve created a few classes which represent a calendar, a calendar column and a calendar stream for a project we’re doing in Rails. These models don’t have matching database tables (does that mean they’re not models?) and I was wondering where they’re meant to go, as /app/models didn’t feel right.

The answer is /lib, which according to the README:

lib Application specific libraries. Basically, any kind of custom code that doesn't belong under controllers, models, or helpers. This directory is in the load path.

I like a tidy filesystem.