This is an older book from the fifties or sixties. A girl tries out for cheerleader at her high school. The school colors are navy blue and white and on the day of tryouts she realizes she is wearing a white shirt and navy skirt that looks almost like the cheer uniform. She is embarrassed about that. She later makes the squad.
Stump the Bookseller
New format, same book stumper solving.
Could be Three Cheers for Polly by Carol Morse.
Polly’s determination to be the best cheerleader brings her unhappiness and failure until in her aspiration for captaincy, she realizes the responsibilities and attitudes necessary for team spirit and leadership.
http://ruthchew.com/about-the-books/Three-Cheers-for-Polly.htm
That’s it! That is my long lost book. Thank you so much. I’ve been looking for this one for years.