If you're asking for Tamagotchi reference materials, try having a look
here. So, do you mean the Holiday Events and Shop Events? Here are a few:
v2, v3, v4, v4.5--a Cake will appear in the Shop on your Birthday.
v2--During November, you can watch your Tamagotchi chase (or was it get chased by?) a turkey.
v2, v3 v4, v4.5--a Turkey will appear in the Shop when you first activate your Tamagotchi. I'm not sure if it appears again later, though.
v4, v4.5 only--on Christmas Eve (12/24) at exactly 10:30 PM, you will see "Santaclautchi" appear on the screen and leave a present for your Tamagotchi, which will remain next to its bed. DO NOT try to see what it is! In other words, no trying to be "sneaky," all right?
v4, v4.5--a giant Egg will hatch on the screen to reveal a baby Tamagotchi during late March and throughout April if your Tamagothci is an adult.
v4, v4.5--during December, your Tamagotchi will occasionally play in the snow (you'll see a snowman in the background). Some people say this only occurs on one day of the month, but this is NOT true--it will happen a few times, particularily if your Tamagotchi is an adult.
Hope I helped.