If I have a bad disposition it's because I have to deal with nitwits who think the untrained 5 year old is the teacher's fault and his 15 year old daughter could fix the problem....with math
I'll tell you a relevant story.
In the world of electronic parts, like resistors and capacitors and such, there is a 'color code', a series of colored bands painted on each part so you can tell what value it is. Black=0, brown=1, red=2, like that.
9 year old children, to get their novice ham radio licenses, have to know the color code. They have to memorize it.
For YEARS, teachers taught about the mysterious character named Roy G. Biv, and none of those poor kids could remember his name or what he stood for (and besides, there were a couple of colors missing).
Then one day, a clever teacher in Brooklyn came up with this one: "Bad Boys Rape Our Young Girls But Violet Gives Willingly".
Instant 100% test scores.
Not only did the students learn the color code, but they learned everything else too.
When you're looking at a pile of resistors trying to find the right one, you can't be looking up the color code in the book each time, you'd be old and gray before you got halfway through. Kind of like adding 2 plus 2, you have to be able to look at yellow-purple-orange-silver and INSTANTLY say "47k, 10%".
I used to play "find the needle" games with my classes. Divide the class into groups of four, give them each a pile of resistors, and tell them to find a certain value. Practice helps.
(Kids are easy, I used to let the winners blow up an electrolytic capacitor by plugging it in backwards, kids really get off on that kinda stuff).