The problem of finding beneficial conditions to integrate students with Special Educational Needs (SEN) is to be aware of their disadvantages for these not to be the fact that deprives them to achieve their goals according to the evaluation system.

 The European Agency for Special Needs and inclusive Education (Watkins, 2007), has been highlighting the need of developing an evaluation system to promote the inclusion and reduce obstacles at all times. After the assessment reports that were submitted by the member countries of the Agency, they concluded that each country should reconsider their assessment systems to find a balance between the assessment processes for supervision and teaching- learning. The aim of this action is to minimize the negative impact on all students and in particular, for those with SEN.

The arise question is: "how to evaluate the group of students with SEN who are enrolled in the conventional educational system?" Because as we have seen before, traditional methods are not enough to provide accurate information of the academic performance of students with disabilities (Black and Wiliam, 2010; Lynn, et.al, 1997 and Torres, 2005). It is necessary to assess other elements that facilitate teacher-student interaction. Farmer, Towles, Kleinert, O'Regan and Kleine (2011) who evaluated students with SEN concluded that the main problem lies on the system that teachers use to evaluate their students’ knowledge.

A proposed alternative assessment that goes along to a proper communication between what students know and what the teacher expects, necessarily involves the creation of a diverse collection of information that evidences such learning. This collection of evidence is a tool for the integration of knowledge in teaching-learning processes (Sá-Chaves, 2000)

A proper collection of information taken at different times of the learning process highlights the importance of the process of acquisition and development of skills, abilities and values. This will help us to verify and implement corrective alternatives to deal with difficulties during the process, under longitudinal and comprehensive collection of data. Furthermore, there have been many researches about the implication of different facts in learning and building self-awareness and metacognition. The findings of Hilda, 1996; Klenowisk, 2003; Mellado, 2005; Rezende, 2010 and Roca, 2012; support the relevance of this approach and emphasise the importance of its implementation to ensure student learning, regardless of their education level and capacity.

The evaluation should transcend the old concepts which  placed it as a simple punitive act of measurement and become a part of the learning process that certifies the individual according to his or her intellectual level. This proposal explores, describes and explains the importance of incorporating alternative assessment strategies in mathematics. It is designed for students with disabilities in inclusive classrooms. This research is based on a methodology  within-subject quasi - experimental cross-sectional design of small groups with variable manipulation in which we pretend, among other things, answer to the question: "How to evaluate mathematics within in a group of students with special educational needs ( SEN ) in a conventional Spanish Primary school?". Similar characteristics were established among two study groups (experimental and control, 5 subjects each): different series of tasks , collected research, the work of mathematic teachers and an alternative program developed by us to evaluate of the subject, using the established evaluation criteria from the Spanish curriculum as a reference for each grade. The program is mainly based on the incorporation of manipulative materials that are made with recycled items and easily engaged with curricular adaptations for each child. The aim of this program is for the children to reach the previously established goals based on the need and requirements of the grade.

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