Some people really like their 22/7: http://www.psychologytoday.com/blog/freedom-learn/201003/when-less-is-more-the-case-teaching-less-math-in-schools/comments#c

Some people really like their 22/7: http://www.psychologytoday.com/blog/freedom-learn/201003/when-less-is-more-the-case-teaching-less-math-in-schools/comments#comment-95513 http://www.psychologytoday.com/blog/freedom-learn/201003/whe... Though come think of it, is this a thing particular to US education? I don't remember ever encountering this in elementary school. I think the early math lessons were just set up never to require irrational numbers, and from 7th grade on (this was somewhere around 1993) we used calculators which gave us PI and trigonometric functions.