Activity-based learning is the process of learning by doing. As opposed to asking students to simply listen and take notes, activity-based learning encourages students to actively participate in their own learning experience through practical activities such as problem-solving and independent investigation. A crossword is a word puzzle and word search game. The games goal is to fill the white squares with letters, forming words or phrases, by solving clues, which lead to the answers. It is used as a teaching tool in various subjects.