Edit: it appears that this is not exclusive to ADHD.
Posting this meme stemmed from my own efforts to explain my thought process when doing math and how it is similar to other people with ADHD doing math, while being different from every neurotypical person I'd talked to on the same subject.
While I didn't make the meme itself, instead finding it in my saves and wanting to share, I did accidentally spread misinformation that I had only backed up with personal anecdotal evidence.
I'll leave this up just so people can see the explanation below but this appears to not be ADHD related and just due to different people doing math in their heads differently...
So, as a childless Xennial, I have to ask... is today's "new math" the same "new math" that people complained about in the 60s?
https://youtu.be/W6OaYPVueW4
If so, that's an awfully long time for something to be shunned as "new."
Truth. I recently got a neuropsych evaluation and part of it was an unexpected (to me) IQ test. And staring me in the face, for the first time in ~30 years, was a few pages of arithmetic problems. Took me a minute to recall how to do decimal multiplication but it did come back to me. Long division? Nope. Had no freaking clue. Given that it was timed I just left blank anything I couldn't work out in my head. Maybe if I had time for trial and error I could have eventually figured it out. But one thing is for sure... the odds of me ever needing that skill again are fairly low.
I had the same thing happen in grade 12. I had a shitty teacher for calculus, so I went to Kumon to try to get help with learning calculus.
They said I needed to do their placement test to figure out where I start on their program, even if I just wanted the calculus booklets. And on it they asked me to manually do decimal multiplication and long division. It took me a minute to remember how to do long division (I'd only done short division for many years, and even that was years ago at the time.) Because it took me so long to complete it, they had me starting on grade 5 math or something ridiculous.
It's predatory what they're doing, imho. A proper test should be to give students a practice version so they can refamiliarize themselves with the content first. Then they'd get an accurate assessment, but they'd rather start students too low so they can scare parents with how far behind their kids are, then rocket the kids forward with lots of easy successes on things they already know so they can show off how amazing their tutoring results are. What a scam.