When third-grade students are allowed to choose books they want to read, which of the following student outcomes is most likely?

While allowing students to choose their reading materials may encourage collaboration, it does not directly lead to the formation of student-organized study groups. Such groups typically arise from specific assignments or projects rather than personal interest in reading choices, making this option less relevant to the immediate outcomes of book selection.

Increased reading fluency can be a potential outcome of allowing students to choose their books; however, it is not the most immediate or direct effect. Fluency is more closely tied to consistent practice and exposure to reading rather than the act of choosing books itself. Hence, this is not the most likely outcome in this scenario.

Personalized goal setting can indeed stem from students' interests in reading; however, it typically requires additional guidance and structure from teachers. Without direct intervention to facilitate goal setting, simply allowing choice does not guarantee that students will engage in this practice, making it an unlikely outcome.