Answer:
Scout first found it strange that Calpurnia was requiring her to dress-up for the occasion. Upon their arrival, she secondly noted that it was strange how she and Jem were the only white people attending. Thirdly, she found it strange that this church had no piano, organ, hymn-books or church programs, as opposed to her own church. Fourthly, Scout found the way in which they sung the hymns strange, due to the prior realization that they had no hymn-books. Fifthly, she was surprised at how aggressive the desire for collections were.
Hope this helps.