The fact that the word "excel" is nowdays synonymous with "spreadsheet software" is exactly the reason why we should NOT teach kids how to use MS Excel. There

The fact that the word "excel" is nowdays synonymous with "spreadsheet software" is exactly the reason why we should NOT teach kids how to use MS Excel. There are many free implementations of spreadsheet software. Kids can get even more experience using different kinds of software, teaching them ways in which software can differ while still being able to do the same things. Ironically, this would probably make kids more skilled with MS Excel, if they were ever forced to use it. There's no reason to teach kids MS Excel in particular, unless you think memorizing positions of buttons is a useful skill in the real world.