>>89124326She was falling victim to the same thing you will one day: having a full time job.
Kim is a globe-hopping secret agent who needs to balance high school, family life, and a career all at the same time.
Let's look at her schedule, just as a hypothesis. The normal highschool day runs from 8 am to 2:45 pm. After school activities, such as cheerleading, run an extra hour and a half. So, her school day ends at more or less 4:15.
This is not counting homework or whatever.
Here's the fun part: suppose Drakken is building a island volcano lair thingy. Kim calls in one of her infinite favors and flies from Middleton to secret volcano island.
Let's use LA to Honolulu as a stand in. Polynesian isle, metropolitan airport: flight time from The extremely west coast of the USA to the middle of the Pacific, 6 hours.
Now, those are six hours she can use to do homework, study, talk with Ron... Know what she couldn't do during those six hours? Use a cell phone. KP ran from 2002 to 2007, long before commercial flights offered wifi, and there was definitely no cell service over the ocean. The Kimmunicator was only really a Ron / Kim / Wade thing, so no talking to friends on that.
So, if Kim just leaves school into a jet plane and flies to the volcano lair, it's after 10 pm by the time she arrives. She fights shego and drakken, spoils their plans, yadda yadda yadda, gets back on the plane and flies home. Suppose the whole affair takes an hour, you can add that to the six more hours it will take to get home, so we're talking about a plane rolling up on the tarmac at 5 am sharp. Just enough time to get home, shower, and doze for about an hour before having to get up and go to school again.
Kim's life is constantly interrupted and intertwined with her job, which prevents her from socializing with her fellow students.