There once was a lady who would cut the ends off her roast, and one day her husband asked her why.
She said she didn't know. It was the way her mom always did it.
So she called her mom and asked her why she cut the ends off of her roasts, to which she replied, "I don't know. That's what my mom always did."
So she called her grandma and asked her why she cut the ends off her roast, and she said it was because she didn't have a big enough pot, so she had to cut it off so it would fit.
Are you teaching certain subjects just because someone else told you to? Have you taken the time to ask why?