Try Naro on a real course.
Pick one of these open courses, from a range of topics, and ask anything from its lectures.
Computer Science
Introduction to Computer Science
from Harvard (CS50x)
Physics
Quantum Physics I
from MIT (Course 8.04)
Engineering
Advanced Thermodynamics
from MIT (Course 2.43)
Mathematics
Linear Algebra
from Harvard (Math 21b)
Biology
Genetics
from MIT (Course 7.03)
Economics
Game Theory
from Yale University (ECON 159)
Psychology
Introduction to Psychology
from MIT (Course 9.00)
Philosophy
Problems of Philosophy
from MIT (Course 24.00)