I need to find two quotes dealing with Atticus's teaching Jem and Scout one of his morals, patience. What are the best quotes for that?

Atticus is an amazing father. As such, he teaches many moral lessons to his children. As you say, patience is one of them. He teaches patience indirectly. It is important to make this point, because there is no single passage that speaks of Atticus teaching patience directly.

Atticus teaches Jem patience when he reads to Mrs. Dubose. All the children know that Mrs. Dubose is an ill-tempered woman, who can be abrasive. However, Atticus wants Jem to read to her. As he does, Jem learns about true courage, but he would not have learned this lesson until he committed to her, which required patience. So, indirectly, Atticus taught Jem two lessons - one about courage, the other about patience. Here is a quote that shows how Jem had to learn patience:

“Yes sir. She wants me to come every afternoon after school and Saturdays and read to her out loud for two hours. Atticus, do I have to?"

“Certainly."

“But she wants me to do it for a month.” “Then you’ll do it for a month.”

We also see this in Atticus's interaction with Scout. Scout is an impetuous girl. She fights a lot when things do not go her way. Atticus forbids her to do so. One of the ways he does this is by making her see things from the perspective of others. This lesson is related to patience. Here is a quote:

“First of all,” he said, “if you can learn a simple trick, Scout, you’ll get along a lot better with all kinds of folks. You never really understand a person until you consider things from his point of view-"

“Sir?"

“-until you climb into his skin and walk around in it.”

Finally, we can say that Atticus's defense of Tom Robinson is also a lesson on patience, because Atticus knows that he will lose. So, he will have to appeal. This, too, takes patience. We can say he teaches by example.