This is kinda of stupid question but I really need to know.

What does class rank mean on ACT score report?? Is it the rank for ACT test takers in your school? or is it the rank for your grades in high school ??

Class rank usually refers to your ranking in your own high school based on your grade point average.

so..50% is good or bad??

Fifty percent is exactly in the middle.

one more thing that I'm confused about.. Let's say my friend took two times. And

how come his lower score has top 25% and the higher score has top 50% ??? Which one is better??

Being in the top 25% is definitely better than being in the top 50%.

Class rank on an ACT score report typically refers to your rank among the students in your high school graduating class. It is a measure of where you stand academically compared to your peers in terms of your overall GPA or grades. This ranking is often displayed as a percentile, which indicates the percentage of students you scored higher than. For example, if your class rank is 90th percentile, it means that you performed better than 90% of your classmates in terms of your GPA or grades. However, it's important to note that not all schools provide class rank information on ACT score reports, so it may vary depending on your specific school. To better understand how class rank is determined at your school, I recommend reaching out to your school counselor or administration. They can provide you with more accurate and specific information regarding class rankings.