A Master Thesis entitled  "The Effect of Using Demsos program on the Achievement of the Tenth Grade Students in Mahtematics and Math Self Concept in Tulkarm Governorate” by “Dua’ Badran” will be defended on Wednesday 27^hDec.2017,  under the supervision of “Dr. Suhail Salhah“ by (9. 30) am  Defense Room (3190(