Didactic

(adj.) Something that is didactic is meant for means of instruction and is intended to teach. More specifically, it’s usually meant for moral instruction. Didactic things are educational, informative, and often moralistic. 
Examples
# “While the soup is simmering, in a small saucepan, heat about 1/2 inch of olive oil over medium heat until shimmering-hot. Working in batches of a few leaves at a time, add the sage to the hot oil and watch them crisp up; it will only take 10 to 15 seconds.”- Chrissy Teigen's Cravings: Recipes for All the Food You Want to Eat
# “If you can keep your head when all about you, are losing theirs and blaming it on you, if you can trust yourself when all men doubt you, But make allowance for their doubting too;...If you can fill the unforgiving minute, with sixty seconds’ worth of distance run, yours is the Earth and everything that’s in it, and—which is more—you’ll be a Man, my son!”- Rudyard Kipling, If