The Effect Of Using Concept Map s On Achieving English Grammar ...

etween the experimental and control groups at ( 0.05 ) level due to theirpre- test achievement in English grammar before the experiment .3.13 The statistical analysisThe data were collected and computed by using (SPSS)StatisticalPackage for social Science , Spearman correlation, Alpha CronbachTechnique and Split –half Technique were used to confirm the test validityand reliability.On the other hand, T-test was used to measure the statistical differences inmeans between the experimental and the control groups due to the teachingmethod.Mann-Whitney Test was used to measure the statistical differences inmean rank between the low and high achievers in the experimental andcontrol groups.Eta square was used to calculate the size effect.3.14 Limitations of the study- The study aimed to develop English grammar achieving for the ninthgraders in UNRWA schools in Gaza governorate .- The study was applied in the first semester of the school year( 2007 – 2008 ) .- The study was limited to teaching English language textbook " Hello 5 "units (6-7-8-9-10) through implementing the concept maps strategy .113