This study aims to examine the usefulness of the online program, Frequency List, as a tool for English teachers to develop paper-based concordance materials for Data-driven Learning (DDL). According to some research, the materials are beneficial for language learners at low-proficiency levels in undertaking DDL since they help ease their difficulties in direct use of the corpus. However, they still have not been used actively in class. The reason seems to be that teachers spend much time and effort to produce the materials, even using sophisticated knowledge of corpus tools. Therefore, this research suggests Frequency List (FL) as a useful tool for English teachers. The program can help users observe target words in multiple dimensions such as part of speech, genres, synonym, and frequencies. To examine its usability and functionality for developing concordance materials, three secondary teachers and one university instructor participated in the program review. They found the functions understandable and easy to use, and also commented that it was helpful to learn the knowledge of the target words and collect necessary concordance examples. It can be concluded that FL is an effective tool for teachers to produce appropriate concordance materials for DDL.