The Combat School is a special mode present in home ports of the Metal Slug series. The player engages in various tasks to improve their skills (and impress the instructors).
- Combat School A: The player plays missions as fast as possible and the entire game in one life. Present in Metal Slug and Metal Slug 2/X and hosted by Sophia and Margaret respectively.
- Combat School B: The player plays through a series of missions. Present in Metal Slug 6 and hosted by Lilly and Mary.
- Combat School C: The player plays through a series of missions and is ranked by their performance. Present in Metal Slug 7/XX and hosted by Cynthia.
- Combat School D: The player plays daily tasks for unit items and MSP. Present in Metal Slug Attack and hosted by Sophia.