512 ants). We eventually needed to write them down to double accurately and quickly made it past a million which had Trainboy cheering, but finished. Dinoguy said he was going to go on to a googol but his interest had waned by a billion. (And I ran out of board space). It was fascinating to watch him think thru the numbers for doubling - checking and considering the next place value. It was excellent arithmetic practice and much more interesting than traditional worksheets. Anyway, just another example of why large numbers are great for kids and why I don't think you should delay introducing them if the kids are interested in them.
I read them the story One grain of rice (one of my favorites) afterward to continue the discussion.Thankfully I took a picture because the next day Princess erased it for us. (The last number is 1,073,741,824.)