1. When you have a big meeting in the evening, and you need photos, it's best not to wait until 3:30 p.m. to ask your mother where the pictures (from the project back in July that the meeting is about) are in the computer and how to print them. Especially when the mother has to pick up two other children from school right at 3:30 and she is still technically at work. And also especially since you slept in until 11:30 a.m. and have been piddling around since getting out of bed.
2. When your mother comes to pick you up from school and asks, "How was your jazz band performance this morning?", know that your knowledge and understanding of standard word usage, a.k.a. "proper grammar," and the situation you are in, a.k.a. in the van with your mother who is a "grammar nazi,"will dictate that you do not answer "we did good" unless you mean that you and the rest of the jazz band members went about doing charitable acts and performing service to those around you. You will answer "We played well." And if you don't, you will be subjected to a very long and intense lecture from your grammar nazi mother on the denotation of "We played good," and how "You know what I meant" is not an acceptable defense or excuse. Plus, your mother is then entitled to any and all Slugbugs that appear on the drive from the middle school to the high school, including that yellow one that is always in the high school parking lot that your mother always seems to forget about.
3. When your mother comes to the high school (right after giving your younger brother a long and intense lecture) to pick you and your friend up to take you home (and while she is still technically "at work," complete with work phone in her purse and schedule of appointment availability on a half sheet of paper in the cup holder) you will hustle your fanny from the entryway of the school to the van and not keep your working mother waiting. You will not stop to talk to friends, you will not wander aimlessly across the cement slab sidewalk, you will wait to root through your Pokemon bag until you get in the van, and you will most certainly not stop to text the person THAT YOU JUST SAID GOODBYE TO. You will also thank your mother profusely for coming to pick you and your friend up, and on the off chance you forgot, you will feel shame when your friend remembers to thank your mother when you didn't.
And yes, grammar nazis are allowed to end many sentences with prepositions because they know that we don't speak Latin, where it is physically impossible to do so, and also "...the yellow one that is always in the high school parking lot about which your mother always seems to forget" sounds ridiculous.