In Dodongo's Cavern there are two Skulltula Tokens that are normally acquired as Adult Link, either for convenience of getting them (Hookshot makes both easy) or speed routing, etc. These are obtainable as Child Link, and are worth going out of your way for when you do the final sweep of Hyrule before pulling the Master Sword. By doing so, you won't need to come back to Dodongo's Cavern as an adult.
To get these Skulltula Tokens early, you will need the Boomerang, some Bombs (more if you cannot Damage Bomb Jump consistently), and (optionally) Bombchu.
In the corridor containing six Dodongo Larvae and the two Armos Statues, there's a point of interest that Navi will gravitate to and turn green. Behind that point is a Golden Skulltula, ripe for the killing.
You'll need to run all the way down the corridor and push an Armos Statue up against the cliff that Navi was floating at. Then, pull the statue away from the wall two steps.
This is where we diverge from the original N64 version. A simple backflip won't get Link onto the Armos Statue like it used to. You'll need to lay a bomb and backflip when it detonates, knocking you onto the statue. This is a Damage Bomb Jump, and takes practice to get good with.
You might want to have the Biggest Bomb Bag if you're new to bomb jumping.
Once you're on top of the statue, get out another bomb (or a Bombchu) and throw it onto the ledge to kill the spider. Again diverging from the original, Link cannot jump high enough to pull himself onto the ledge, so we need to get creative with the Boomerang.
Here's where the hard part begins. You'll need to have a good understanding of how far the Boomerang flies before turning, and how to handle it. After throwing the Boomerang, if you move to the left or right just before it turns, it will turn in the direction you're holding. It's possible to do this with small movements on top of an Armos Statue, too.
You'll need to hop off of the statue and move it a little further west and south. Here are some pictures taken with a phone to illustrate where zlg was able to fetch the token. (Sorry for the quality, will be better once I install CFW and can screenshot anything)
Add pics.
Once you're on top of the statue, aim the Boomerang at the farthest corner to the right but still inside the alcove. Then be sure to steer it left. After a few tries you should be able to get it to nab the token on the return trip. If you keep clinking the wall, move the statue one step away, Damage Bomb Jump back up, and try again. (Nobody said this was easy!)
This one's much easier to get to since the game provides an easier way to get it than resorting to crazy Boomerang throws. You'll need to progress through the east side of the dungeon "backwards" by taking the elevator column in the main room and backtracking until you come back to the traps and the top of the blast column room, where there are vines and a White Skulltula lurking. Take the downward path to the left and follow it. You'll see there are vines on the side of the column that would normally fall down if you blasted it from below. Climb them and the Golden Skulltula is yours! You can backflip to obtain the token, or use the Boomerang.
This works because certain puzzles in dungeons are reset upon leaving, like the blast column.