This study aimed at identifying the effect of teaching geometry using Geometric Sketchpad Programme on geometric thinking and geometric drawing skills with grade eight basic education class students. The study sample consisted of (121) male and female students who were divided into two groups: the experimental group of (62) students who were taught the unit of Geometry using the Geometric Sketchpad Programme and the control group of (59) students who were taught the same unit using the traditional method. The equivalence of the two groups among the variables of the study was measured before the study was implemented. To measure the extent to which the programme was effective, the researcher designed three tools: an achievement test , a Geometric thinking test, and a Geometric drawing skills test. The validity was measured by agroup of validators. The reliability of the three tools was measured by applying them with a group of (30) female students of Grade 8 as an external sample. The results revealed that the reliability was (0.73, 0.82, 0.83) respectively; measured by Cornbach's Alpha. The researcher used the means, the standard deviations and the T- test to analyse the data. The study revealed that there were statistically significant difference at (a < 0.05) between the grades means of the control group and the experimental group in the post achievement test, the geometric thinking test and the geometric drawing skills test after studying the Geometry Unit in Grade Eight using the Geometric Sketchpad Programme favouring the experimental group. Based on the results, the study recommended using the Geometric Sketchpad in teaching geometry.