As a guy with a university degree in science and math, I recommend using UN-natural language at first. That is, always translate the math symbols into the same English words every time. "times" "equals" "plus" "minus" "divided by". Later on, you could add more natural English wording. "Natural English wording", by the way, is often regional, so if you value British English or American English more, you may want to ask the right speakers. Regarding questions, I'd say usually go with "What's ___?": "What's 3 times five?" It would also be natural to say "3 times five equals ...?" , expecting your child to finish the sentence.

Hi there, (2+3=5) I would say ‘two plus three is five.’ Another common native alternative to ‘plus’ is ‘add’. eg. ‘two add three is five.’ ‘Two plus three equals five’ is also frequently said. ‘What’s two plus three?’ is perfect. (5-3=2) Again, ‘five minus three is/equals two.’ ‘What’s five minus three?’ is perfect. (3x5=15) My most natural phrase is ‘three fives ARE fifteen’. ‘Three fives IS fifteen’ doesn’t make sense grammatically. ‘Three times five equals fifteen’ is also good. I would personally never say ‘five by three’ to a younger child, only to older teenagers. ‘What’s five times three?’/‘Five threes are...?’/‘Three fives are...?’ is how I would best ask the question. (6/2=3) All suggestions fine. (10/3=3... 1) I would tend towards using ‘equals’ for this one. As you can see, I find it more natural to use ‘is/equals’, rather than ‘makes’. However, makes is also definitely acceptable. Hope this helps!

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