There are some interactive books/courses/sites that are nice. They don't necessarily use 'layman terms' like that 100 year old calculus book:

http://oli.cmu.edu/courses/free-open/statistics-course-detai... http://www.socr.ucla.edu/ http://cast.massey.ac.nz/core/index.html?book=general https://www.kno.com/book/details/productId/txt9780983804905