Most children take part in after-school clubs.(Go for it八下U.

Most children take part in after-school clubs.(Go for it八下U.2 Reading)
What club do you want to join?(Go for it七上U.10)
take part in和join可以互换吗?为什么呢?

不可
join\ join in与take part in的区别
一、take part in一般是参加什么活动,也可以是会议之类的
而join则比较严肃,一般是入党才用,或是你正在做什么,邀请别人一起加入,可以说would you like to join us?
join和 take part in 二者都有“参加”的意思,但用法有所不同.
二、join多指参加某组织,成为其中的一个成员.而take part in指参加活动.
join指加入某党派、某组织或某社会团体,以及参军等,还可表示参与某种活动.例句：
①I will never forget the day when I joined the Party.我永远也忘不了入党的那一天.
②Will you join us for dinner?请你和我们一起吃饭好吗?
join有两个用法：
(1)指加入某个党派,团体组织等,成为其成员之一,意为：“参军、入团、入党”等.如：
①When did your brother join the army?你哥哥什么时候参军的?
②She joined the Young Pioneers.她加入了少先队.
(2)和某人一道做某事,其结构为：join sb.in (doing) sth.,根据上下文,in (doing) sth.也可以省去.如：
①Will you join us in the discussion?你参加我们的讨论吗?
②He'll join us in singing the song.他将和我们一道唱歌.
③We're going to the East Lake Park on Sunday.Will you join us?
我们打算星期天去东湖公园.你跟我们一道去好吗?
take part in指参加群众性活动、会议、劳动、游行等,往往指参加者持有积极的态度,起一份作用,有时与join in可互换.例句：
①Will you take part in the English evening?同我们一起参加英语晚会好吗?
②All the students took an active part in the thorough cleaning.所有的学生都积极参加了大扫除.
③We should take an active part in school activities.我们应该积极参加学校的活动.
take part in 指参加会议或群众性活动等,着重说明句子主语参加该项活动并在活动中发挥作用.如：
①We'll take part in social practice during the summer vacation.
暑假期间我们将参加社会实践.
②We often take part in physical labour.我们经常参加体力劳动.
【注意】take part in是惯用词组,part前一般不用冠词,但part前有形容词修饰时,要用不定冠词.如：
①Lincoln took an active part in polities and was strongly against slavery.
林肯积极参加政治活动,强烈反对奴隶制
join in sth./ doing sth.意为“参加”,后面接的宾语一般是表示竞赛、娱乐、游戏等活动的名词或V-ing.例如：
Can I join in the game?我可以参加这个游戏吗?
They all join in singing the song.他们一起唱这首歌.