Udemy offers The Inexplicable Universe with Neil deGrasse Tyson Online Course for $90. Coupon code "APRILUDMY" knocks it to $10. That's tied with our mention from three weeks ago, $80 off list, and the best deal we could find. It includes three hours of on-demand video, with a certificate of completion at the end.

Can't get enough of Neil deGrasse Tyson and/or the universe? Also available is the My Favorite Universe by Neil deGrasse Tyson Online Course for $10 via the above coupon. That's tied with our mention from three weeks ago, a $160 savings, and the best we could find. It includes 6.5 hours of on-demand video, with a certificate of completion at the end.