## Guidelines for Origami Difficulty

### Simple:

For students: No previous folding experience is required to take classes rated simple.

For teachers: The models should have mountain and valley folds only, be relatively forgiving of small errors, and have reference points for everything. Even the most basic of maneuvers and techniques should be explained, i.e., say 'fold bottom edge to top edge, which is a book fold,' rather than 'fold a book fold.'

Examples: Swan, magazine cover box, jumping frog, sailboat.

### Intermediate:

For students: All of the above, plus you should know how to fold a bird base from memory, and be good at inside reverse folds, outside reverse folds, and basic sink folds.

For teachers: You can assume that your students know basic terminology, but be prepared to reinforce. For example, you might say something like: 'fold a colored preliminary base, that is, colored side up fold two diagonal folds, then white side up fold two book folds.'

Examples: Flapping bird, crane.

### Complex:

For students: All of the above, plus you should be an experienced folder, be comfortable folding from diagrams, and be able to follow intricate sequences of precise moves.

Complex models might have "collapse" moves, where many creases come together at once. They are also commonly very sensitive to folding errors, so that if you do not fold precisely early on you won't be able to complete the model.

For teachers: Before the class starts, explain what will be expected in the class, such as folding something precisely into a grid of 64th's, and give the students the opportunity to change to another, simpler class. You should not have to explain any standard maneuvers, and should be able to state an objective and let the class proceed, such as 'please fold your paper into a grid of 64th's.' But be very aware of your students' progress, because a simple error early in the folding progression may result in inability to complete the model.

Examples: As defined by the creator of the model.