There's Tomatoes in Ketchup?!?!

One night when I was about 9, and my sister, 12, we decided to beat our boredom with a game. We took random bottles and jars out of the pantry and quizzed each other on "Guess the Ingredients!" Quite a clever game I think......

I did pretty well until I had to guess the ingredients for ketchup. I got all the ingredients except one. Tomatoes. I had no idea that tomatoes were the main ingredient in ketchup!

Why am I telling you a story about my childhood? For me, it illustrates how my brain functions in various situations- trying to put it all together, make sense of it but often missing the "main point/ingredient." Here are a couple of examples

School assignments/tests: I poured lots of time and energy into studying and doing homework, but I rarely got above a "B" It was very hard for me to grasp the main point of the assignment/what the teacher was looking for OR I could quote definitions/examples for a textbook, but had no idea how they fit into the main ideas for a test.
Another example- When there was/is a lot to do, it's harder to priortize. To determine the "main ingredient" that needs to be done first, is most important, etc.

Thankfully, there are strategies available to better find the main point/ingredient, etc. Here's some that have worked for me.
School: when possible, turn my asssignments in early for feedback to see what points I am missing, what gaps I need to fill in. When preparing for tests, specifically ask the teacher, "why is this important? How does this fit with the main goal?" Not all teachers have been receptive to this, but many have!
For prioritizing: I put everything to do into the electronic calendar on my phone (just a regular cell phone), often a day before it's due. I check it every morning for what needs to be done and see what I can get done that day. Plus, there's alarms that go off if I forget what needs to be done.

What strategies have worked for you? I welcome any feedback, questions, comments, etc. This is a topic I'm VERY open to discussing, so no need to be hesitant about asking me questions!