This study examines whether students’ ability in mathematical writing and understanding gained from teaching through ‘think talk write’ strategy is better than students’ ability gained from conventional one. This study also examines students’ ability in mathematical writing and understanding from gender aspects. Using quantitative design, data was taken through documentary study, questioner sheets and observation. Data was analyzed using two ways ANOVA. Result show: a) the ability of students in mathematical writing and understanding gained from teaching using ‘think talk write’ strategy is better than the ability gained from conventional one; b) the ability of female students is better than male students; and c) Think Talk Write strategy can improve students’ mathematical disposition ability.