I would say mine is the Miraculous Journey of Edward Tulane. My teacher read it to the class in third/fourth grade and I fell in love with it. It might be because I loved dolls and stuff like that and related to Abilene. I loved seeing Edward going on all of this adventures and I believed for the longest time that he was like a character in Toy Story. I think my favorite part was when he was with this brother and sister. Although many people don’t like it due to its non-kid friendly topics (abuse, manipulation, death),the book just reminds me a simpler time in my life and when I just started to realize reading was fun.
The Mysteries in our National Parks series, which you probably haven’t heard of because you were reading Goosebumps! Both share a similar-ish genre and competed for the same shelf space in our library.
Not sure why I liked them. Each book was written in easy-to-understand narrative prose, had unique side characters, and ended with an easily digestible moral.