Use the code APRIL25OFF to cut 25% off Select Online Courses in topics like iOS App development, digital photography, SAT prep, freelance writing and more at Udemy. Over 12,000 courses are available with prices that drop to as low as $15 using the code, like this Power 800 SAT Math Course that was originally $20. Every course offers unlimited, lifetime access to the lectures and materials on both a computer and mobile and comes with a 30-day money-back guarantee. There is no sales tax.