Assessment in the Montessori school is done through a qualitative analysis of children's performance, not by classifying and comparing students by grading. Montessori assessment includes: daily observations, daily progress sheets, periodic report describing the child's overall development (social, academic, emotional), strengths and weaknesses and ways to improve the weaknesses, portfolio of works and projects of the child, weekly or bi-weekly meetings with the children, in which they record together with the teacher the activities and skills acquired during that period. 

The Montessori teacher carefully makes notes to ensure that students are shown the right presentations when they are ready to receive them. Daily observations and detailed notes help the teacher to plan the individual lessons that follow, for each child. 

The Montessori teacher makes notes and observations for the lessons presented, the work done by the child after the presentation of the lesson, the child's progress, the daily diary kept by the child, difficulties encountered by certain children and how these difficulties were overcome, individual meetings with each child (once a week or every two weeks).

The assessment, closely related to children's observation, is an ongoing process in a Montessori class. It is one of the essential features of the method. Observing a child's repeated behavior is a way to record the changes that occur in his development.

The teaching methods used in Montessori and the learning methods provide opportunities for formative assessment. Here are some examples:

  • As the lessons are presented individually or in small groups, the teacher can easily observe and write down the level of understanding of each child. Before the lesson is over, each child is given the opportunity to show how the material is used. Any child who needs to be taught the same lesson again can participate on the next occasion, together with a group of children, in the same presentation. 
  • Many of the materials have a built-in control of error, so it is easy for both the child and the teacher to know if the information, skills and purpose of the material have been mastered. The design of the material itself makes the student himself able to figure out if something is wrong. He will then know that he will have to ask for his presentation to be repeated so that he can understand it better.
  • The fact that students choose their own activity says a lot about their interests and abilities at a given time, which the teacher observes and notes.
  • During the regular individual meeting with the teacher once a week or every two weeks, the child over the age of six becomes a co-evaluator of his / her own activity, together with the teacher. They analyze together the child's daily diary, the portfolios and the completed projects, establish together what is to come and discuss the possible difficulties that appeared along the way.