Never mind 30 years from now, the advent of electronic calculators on phones, text messaging using abbreviations, automatic spell check, using google maps to navigate etc already means that the younger generations ability to perform mental arithmetic, write complete sentences without using spell check etc. is diminishing day-by-day.
How many of you under 30 know about, never mind use, log tables, slide rules etc? Or can even use actual physical maps and know the meanings of various symbols/legend?