This study aims to assess the impacts of the Catholic Office for Emergency, Relief and Refugees (COERR) Writing Project (COERRWP) on students' attitudes and their writing performance in correlation with age, gender and language proficiency. In the first stage, a study was conducted to assess 45 students’ actual writing performance based on score analysis of their writing test through 2011 to 2014. In the second stage, a quantitative survey questionnaire was administered to a further 80 students from the initial cohort of intermediate, upper and advanced levels. The study found that the COERRWP was effective in improving macro performance such as paragraph or essay structures rather than micro performance or the accurate use of lexico-grammar.