Children take teasing, lying, and sarcasm at different levels depending on their personality and age. In my case, I never did learn to appreciate sarcasm or "pretend lying" (the kind where the person tries to get you to believe what they're saying, then laughs at you for being gullible). I can take some teasing, but I prefer people make actual jokes if they want to be funny.
For most people, and kids in particular, teasing is safe and sometimes funny when the subject isn't self-conscious about the topic - but when the target is insecure about a particular aspect of their bodies or their lives, teasing is almost never "fun." You can tease me about my brains, love of computer games, or my glasses - but don't "tease" me about my tummy/thighs/chest, my sex life, my weight, my career plans, or my desire to have kids someday soon. Those are things I'm insecure about (to one degree or another), and even my DH wouldn't be "funny" if he made a crack about any of them. I only appreciate sarcasm/"pretend lying" that doesn't fool me for a second - saying "You really should read more!" is fine (nobody who knows me thinks I don't read enough!), but saying "That call was your mom, your brother was in a car accident. Kidding! No really, she was just saying hi" is NEVER funny.