This book centers around a young female protagonist (I think middle-school age) who learns to bake bread and struggles in science class. At one memorable point, she uses mayonnaise in her hair because she heard it’s a good conditioner. She has both an older sister and younger brother. Near the end of the book, she is able to do a bread making demonstration for a science fair/science assignment.
I believe I read it somewhere between 2005-2009, but the cultural references in the book make me think it was from the 90’s or early 2000’s?
Note from Molly: this one is on the tip of tongue, I definitely recognize the mayo-conditioner plot!
Lost Classics of Teen Lit: Name That Book! 
I am not positive, but I know I read this book too, and I have a few suggestions for you to look at:
Tough-Luck Karen by Johanna Hurwitz (my money’s on this one)
Karen Kepplewhite Is the World’s Best Kisser by Eve Bunting
Hurricane Elaine by Johanna Hurwitz
(Daisy, who can’t remember her password to this site)
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I totally remember this…she describes the clumps of mayo falling from her hair— I’m pretty sure she hated mayonnaise (or maybe eggs?) but her little brother talks her into trying it. I don’t know the title but I know i’ve read it.
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I remember this plot, too, but not the title. I would estimate mid to late 1980s publication. I read it in middle school, I think, so it had to be mid-90s or earlier, but I remember it being an older book at the time I read it.
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Tough Luck Karen by Johanna Hurwitz, without a doubt. This was an old favorite of mine that I read over many times.
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I think you’re right! Our children’s librarian was a big Hurwitz fan, but I never really got into her so that was the only one I read.
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pretty sure it’s Tough Luck Karen! Love this website
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