☆the Teach and Learn Approach☆
・This way will go smoothly. Because students can understand easily what teacher tells them.
・Students will be able to review the words easily when they forget them.
・This way may be bored with studying. Because This is a stiff and formal way.
・Students may forget the words easily. (I think that it is one thing to understand the meaning, another to memorize the meaning.)
☆the Learning through Input Approach☆
・Students will be able to memorize the meaning with joy, because it is like a quiz.
・Students will think and study voluntarily more than the Teach and Learn Approach. Because it is like a quiz and they don't know when teacher calls them.
・Maybe, some students can not catch up with the pace of the lesson. (Teacher sometimes have to check the understunding of students.)
Lastly as a junior high school English teacher I would favor a hybrid. Both methods have different strengths. And students or classes also different. (For example silentry, noisy,restless and so on.) So I think that teacher should change these methods to the state of students.