Curriculum is the sum of the child's experiences in a particular educational setting.
Montessori is an education as an for life itself.
The Montessori curriculum is found in a blend of the Montessori albums (lesson plans are the album pages) and the needs of the particular child before. The Montessori approach provides the keys for the universal child and time/resources to follow the interests and needs of the very unique individual child before you.
For more information on the key aspects of an authentic Montessori experience, pick up a Keys of the World or Keys of the Universe primary or elementary theory album.