As a child, I became so frustrated when trying to memorise the times tables, I would try slapping my head with an open hand to force the memory cells to work harder. Well intentioned maths teachers would struggle to explain using coloured wooden blocks whilst I looked on, sucking the red dye out of the longest ones. All through primary school I managed to struggle along by singing aloud different counting sequences to memorising the song in my short-term memory then promptly writing them down (as I would quickly forget) or relying on brute force calculations by counting.
At secondary school, I could readily deconstruct the sine rule, scribble up a crude Schrodinger wave equation or fill in a periodic table. It was those blasted times tables that haunted me. I have since realized that I am not alone and share this malady with Dr Karl who also like me, also has a problem matching names to even familiar faces. I blame this growing up on a dairy farm as I have no problem telling cows or roos apart.
Then I learned some finger counting and multiplication strategies such as Chisanbop. These suited me well through my senior years as I could undertake these basic calculations "under the desk" without anybody knowing.
Having a calculator at uni was a blessing that propelled me forward. Now when I am teaching maths, I can quietly do these finger calculations whilst facing the white board or even behind my back.
I share this with students that struggle with their times tables, but only when they can snatch a pebble from my open hand.