클래스카드 is a free educational app developed by CLASSCARD Inc. It is designed to provide effective vocabulary learning and testing for English language learners. With over 11,000 teachers and 2.3 million students using the app, it has gained popularity in South Korea.

The app offers a scientific, three-step memorization method that makes learning vocabulary more enjoyable for students. It includes a collection of 700 official word lists from top publishers like NE능률 and 웅진, which are available for free. Teachers can create automatic tests that students can take at home, and the results are instantly available in real-time reports. The app also includes features for speaking, sentence practice, listening exercises, and dictation.

For students, the app allows them to memorize and submit tests based on the sets provided by their teachers. The scientific learning method ensures that vocabulary is memorized effectively. Once the sets are downloaded, students can study offline without worrying about data charges.

Overall, 클래스카드 is a valuable tool for teachers to save time and provide effective vocabulary learning for their students. For any issues or inquiries, users can contact the customer support through the "Menu-Customer Service" option in the app.