thinkhuman

Overwhelming amounts of research that show the last thing pre-7-year-olds need is math training. In several countries--like Finland--math and reading come later, yet they score higher than most every other country in the world in math and reading.

Given this, why in the world introduce calculus at an age when it's convincingly wrong for brain and emotional development?

Edit: For angry-responding folks that want "proof", a few quick examples:

https://www.psychologytoday.com/blog/freedom-learn/201505/early-academic-training-produces-long-term-harm

http://www.scholastic.com/teachers/article/what-happened-kindergarten

http://www.alfiekohn.org/article/early-childhood-education/

https://www.psychologytoday.com/blog/freedom-learn/201506/how-early-academic-training-retards-intellectual-development

You seem to have misunderstood. Also:

https://www.psychologytoday.com/blog/freedom-learn/201505/early-academic-training-produces-long-term-harm

http://www.scholastic.com/teachers/article/what-happened-kindergarten

And, Finland's educational system is a real-world, large-scale, long-term example that supports it.