Pokemon Snap

Go to the Cave level and follow it almost to the end. When you see the Jynxs play the Poké Flute. The Jynxs will perform a ritual dance, and the ice egg will float in the air and hatch into Articuno.

Take photographs and throw Pester Balls at the Shellders in the River level. If done correctly, a Cloyster will appear later in the level.

Here's how to see different credits then the ones when you photograph Mew! All you have to do is finish your Pokemon Report, then Prof. Oak will congratulate you. Voila! Different credits you'll only see once!

Diglett appears on the left side of the Tunnel level, next to a Pikachu.

The three Bulbasaurs at the beginning of the Cave level are really Dittos. Throw some Pester Balls at them to change them back into their true form.

When the Doduo runs across at the start of the Beach level, hit it with an apple. It will fall down stunned. This allows you to get a good picture of it, fainted across the middle of the track.

Throw pesterballs into the whirlpool in the Valley level.

Take a photograph of Eevee just after turning the pink ball into Chansey. It will jump into the air gleefully, and you will get extra points for a happy pose.

Look to the right in the middle of the Tunnel level to see Electabuzzs standing in front of large screens. Throw apples at one of them and it will walk approach use a Thundershock attack. Take a photograph while it is emitting energy for extra points.

After completing the Valley level by hitting the Mankey on the switch, Professor Oak will tell you to take photographs. Here are their locations:


Kingler
On the Beach level, after passing Pikachu, turn around and take a photograph of the rock with seaweed that resembles a crab.

Pinsir
In the Tunnel, wait until Zapdos has hatched and turns on the power. When you pass the Electabuzzes and Pikachu, look to your right to see Pinsir's shadow on the wall.

Koffing
In the Volcano level, throw a Pester Ball into the small volcano to the left of the first Rapidash that appears. Smoke in the shape of Koffing will appear.

Cubone
In the River level, play the Poké Flute in front of the sleeping Vileplume. The smoke will disappear and a tree in the shape of Cubone will appear.

Mewtwo
In the Cave level, after hitting the two Koffings chasing Jigglypuff with apples, turn around to the left while near Weepinbell and to see some bright crystals/stars. Take a photograph and it will turn out to be Mewtwo.

Dugtrio
In the start of the Valley level, take a photograph of the mountain behind the Mankey.