You don’t have to be a genius or complete any assignments. All of these books are fairly accessible to the average reader.
I read the majority of them in high school, and they set me (a dyslexic student with undiagnosed adhd) up for a lifetime love of mathematics.
Many of these books could also be categorized as popular science or history books. A couple of them, such as Surreal Numbers and Flatland, are actually fiction!
2003 • 3 Readers • 255 pages • 2
2002 • 5 Readers • 280 pages • 4
1959 • 2 Readers • 200 pages
2001 • 15 Readers • 320 pages • 2.5
2010 • 7 Readers • 296 pages • 5
2003 • 32 Readers • 335 pages • 4.3
2012 • 56 Readers • 336 pages • 4.1
2012 • 81 Readers • 421 pages • 4.1
5 Readers • 4
2021 • 10 Readers • 225 pages • 4
2009 • 7 Readers • 528 pages • 5
2008 • 88 Readers • 252 pages • 3.9
1884 • 264 Readers • 99 pages • 3.6
1993 • 1 Reader • 227 pages
2000 • 5 Readers • 4
2002 • 17 Readers • 305 pages • 3