All of the three words could be verb and noun. 安排arrange/arrangement To arrange resources (time, human etc.)for a specific work,event or a period of time. 例句： 这是对春节期间的放假安排。 This is the scheduel of the Spring Festival holiday. 老板安排小王去联络客户。 The boss let Wang to contact client. 计划 plan A relatively compelete and considered plan that include the goal, method, shedule etc. As a verb it is more formal and used in written Chinese. 这是下一学期的学习计划。 This is the study plan of next term. 政府计划建设一座医院。 The government plans to build a hospital. 打算 intend to do/intention It is more casual and informal. For someone intend to do something or just think about to do something. 我打算明天去书店。 I want to go to a book store tomorrow. 她没有去工作的打算。 She does not have the intention of working.

1) 安排 can be a verb or a noun and it is mainly used to express the meaning of "to arrange" or "arrangement". It's also commonly used to make an actual plan, for example, for your trip abroad. For example: "我们还在安排我们的台湾旅行。" “We are still making arrangements/plans for our trip to Taiwan.” 2) 计划 is most often used as a noun which means "a plan” or "a project" or even "a program (of activities)". For example: "计划突然改变。" (There was a sudden change of plans.) 3) 打算 is the most neutral and can also act as a verb and a noun but 90% of the time it is used as a verb. For example: "明年我打算和我朋友一起去美国旅游。” (Next year, I'm planning to travel to the US with my friend.)

All the same. Don't bother.

“ 我想要早点儿制定旅行计划，但我还不知道暑假的课程安排。所以我打算去问一问老师。”