.

This study aims to find out the words that fifth grade students in the province of Manisa use in writing and the frequency of the occurrence of these words in their written works. The participants of this study are one hundred fifth graders living in the province of Manisa. In examining the words employed by the participant students in writing , the study considers the following variables: gender of the participants, whether they attended preschool, jobs of their parents, number of the siblings in their families, ages of the siblings, how often the participants read a book or a newspaper at home or at school, the amount of time they spend watching TV, forms of writing they produce, how often they do writing exercises, and whether they live in a village, town or a city. The one hundred participants of this study were first asked to write a composition on the kind of summer holiday they wanted to have. The participants were then given a Vocabulary Test. Lastly, they were asked to write informational compositions on any of the topics offered to them. The findings of this study are gained by analyzing the collected data through SPSS 17. The findings of this study reveal that the following factors have a considerable influence on both the total number of words the participants use in writing and the number of different words that occur in their written works: attending preschool, jobs of the participants parents, forms of writing the participants produce, number of their siblings, whether they live in a village, town or a city, and how often they do writing exercises. However, gender of the participants, amount of time spent watching TV, ages of the siblings in their families, and how often the participants read a book or a newspaper do not have a significant effect on how many words the participants employ overall in their writings or on how many different words they can utilize in them. Statistically analyzed, the findings of this research indicate that out of a total of 27,933 words used by the participants, 3,592 are different from each other. This study concludes that when male and female students are offered equal educational opportunities and when it is made sure that they live in similar social conditions, the vocabularies utilized by them in writing are identical in terms of both the total number of words and the number of differents words possessed. The study also shows that students living in the towns in the province of Manisa employ richer vocabularies in their writings than those living in the villages and city of Manisa. Finally, students who attended preschool use a significantly larger vocabulary in their written works than those who didn?t. Key Words: vocabulary, frequency of word occurrence, actively used words