马克·科茨沃尔兹 是一名在家上学的孩子，曾在“家庭与社会”中参加并赢得第15届南方公园年度拼字比赛。
背景
马克在他的家庭学校生活中非常受庇护，直到参加拼字比赛他都没有看到过外面的城镇。马克想要上公立学校，恳求他父亲给他机会。
马克被关在巨大的仓鼠球里上学，他受到了其他男孩的欺凌，并被绑在长椅上。尽管他父亲希望他重返家庭学校，但马克说服父亲让他继续上公立学校，参加学校舞会。
在学校舞会上，马克因痛揍了将丽贝卡变成荡妇的凯尔·布罗夫洛夫斯基。而给其他男孩留下了深刻的印象，他们都想和他一起出去玩，并将他纳入自己的圈子。
尽管他们的父亲试图干预并将他们带出舞会，但马克说服他的父亲让他们上公立学校，因为他们两个有一天仍将不得不面对糟糕的事情，不如现在就面对它们。
自从剧集播出以来，马克也曾再次出现在动画中，在“混沌教授现身”中客串，在“亡命宽容营”作为被送往营地的孩子里（首次出现时）的潜在的第四位朋友，和“ 幻想大陆·上”，出现在在卡特曼的聚会上。
外观
Mark wears a deep green pullover sweater, with a white dress shirt and a black tie underneath, and black slacks. His hair is dark brown and slightly wavy, with a parting in the bangs.
个性
He appears to be the older of the two siblings, and is the more outgoing one, curious of what life was like outside their home and eager to explore the public school, wanting to see what other boys were like.
Though he is incredibly intelligent, he was also naive in a few ways; seeming astonished that "friends" would call each other names and fight, that the boys seemed to "like, yet hate" Pip at the same time, and how the other boys laughed at Kyle for liking Rebecca. Though he was continuously bullied by the others and found himself duct-taped to a bench, he was unconcerned and grew more curious each time.
Despite his parents' objections, he remained eager to explore the outside world and ultimately gave a speech explaining why it was all right for him to stay in public school.
He seems quite protective of his sister, beating Kyle up after seeing what he had inadvertently turned her into, which the other boys then considered him to be "badass" for it.
By the end of his debut, he was finding his way into fitting in with the other boys, calling Stan a "gaywad" in response to being called "nerdo".
出场
- "家庭与社会" - Mark and Rebecca win the spelling bee. Mark is intrigued by other kids and wants to join public school.
- "混沌教授现身" - Mark is one of the contenders to replace Butters, but doesn't make the cut past the first elimination round.
- "亡命宽容营" - Mark is seen at the camp when the boys first arrive.
- "失恋的斯坦" - Seen in Raisins from the back.
- "自负警告！" - Mark is seen at party.
- "幻想大陆·上" - Mark appears at Cartman's party.