Friends Or Studying

So, my friend came over to my house and asked me if I wanted to hang out someplace, but I knew I had a science test the next day. I told her that the test was important to me and if I was to fail that it can effect my grade. I told her that I was going to stay home and study for I can pass the test. I know that school is more important than hanging out and waiting for the last minute to study. She under stood from where I was coming from, so she left and went out with someone else.