Chutes and Ladders ('Snakes and Ladders' in England, and 'Hoses and Pickets' in Canada) is fun to play for 5-year-olds, but it quickly loses its value once the players realize that the game is entirely deterministic.
Perhaps it is because we enjoy the illusion of choice and freedom of will that we prefer games that allow us to make mistakes in judgement, rather than simply following the directions from the omnipotent, yet random force of a die or spinning wheel.
So, to make the game more enjoyable, here are some variation that older players might enjoy.
This is the most crucial variation in that it adds the possibility of choice to each turn.
As in parcheesi (or Sorry!), on each turn, a player may choose to simply advance a piece toward the goal, or play defensively by knocking out the piece of an opponent.
If playing with a younger child, you may wish to start with only two tokens per player, to simplify the strategizing and make it easier for them to grasp the concept of a non-deterministic game (at say, 6 years old, most children still only play deterministic games such as Candy Land and War).
With older players you may wish to use up to 5 tokens per player.
This option is also quite fun with more than two players, as the social aspect increases, with alliances forming to collectively defend against whomever is in the lead.
When knocking out another piece with one of yours, one variation is to knock them completely off the board, so that the piece has to start again at '1', but another option is to knock the piece back to nearest chute.
There are two version of the winning condition.
One is to get all tokens by a given player to the finish, the other is whoever is first to get just one piece to the finish wins.
Baricade seems more popular in Europe than in the US, but is quite a good game.
What separates it from parcheesi or backgammon is that the board begins with 10 barricades that impede progress - pieces cannot cross over them.
The only way to remove a barricade is to land squarely on it, at which point the player that has done so can move it anywhere on the board (except for the first row of tiles)
In Chutes and Ladders, the Barricade variation means that at the beginning of the game, each square that is at the top of a chute holds a barricade that can only be removed by landing on it (landing on a barricade at the top of a chute or bottom of a ladder means the token does not travel down the chute or up the ladder).
Alternately, the barricades (10 or so) can be divided among the players, who can choose to play them on a given turn rather than rolling the die.
In this version, two dice are used, and a player can move two pieces, one for each die, or move one piece the combined number of spaces. (if a 5 and 3 are rolled, the player can move one piece 5 and another 3, or one piece 8 spaces)
So far, the variations are still somewhat chance-oriented, but that can be mitigated by removing the die and having the players decide how to move each piece. On any turn, a player can move one token up to 6 spaces, with the side-rule that no captures can take place in the first row of tiles.
This rule can be modified so that any single move cannot cross rows (a piece cannot move from one row to another unless the token is in the last tile of the row). This helps set up 'choke-points' for defensive play.
Another variant is to play with chess pieces, with special rules.
Instead of simple tokens, use the pieces from a chess set, specifically the rook (castle), bishop and knight
:the rook cannot be passed over by any other piece, though can be removed by landing directly on it
:the bishop is exempt from sliding down chutes
:the knight can climb both chutes and ladders
Another variant is the 'Roshambo' (rock, paper, scissors) version, where rooks can only take bishops or other rooks, bishops can take only knights or other bishops, and knights can only take rooks or other knights.
Camino del Rey
In this variation (also using chess pieces) one of the tokens is the 'King' and it is the king that must make it to the end, not just any of the tokens.
The play would be like the Parcheesi variation, except the strategy would of course change as the focus becomes on the king.
One last rule that can be used with any of the others is that once a piece is captured, it is removed from the game, rather than able to start again. This only makes sense when playing with a large number of tokens per player (around 15).
Most of these variations can be combined, in fact a rich and complex game could be played by combining all of these special rules together.