user7002: I'm teaching my 5 year old daughter basic chess. While she's kind of interested, I feel the material, such as how the pieces move, mate in 1 puzzles, basic KQ and KR checkmates, etc, is a bit boring to her.
This answer on another question presented an interesting variant call Rescue Snow White. It combines piece move training with some fun story.
Can someone can suggest other variants similar to Rescue Snow White that motivate children to learn chess? Being fun on the chess board is the main requirement, while the training value is an optional bonus.

user7002: Chess fighters
Idea is taken from the battle chess game. 
Play normal chess. When piece A takes piece B, the two players play a street fighter (or whatever fighting game) match. The defender can only move or block for the first 30sec of the match. Whoever loses the match loses the piece. King doesn't fight, automatically wins if taking a piece, but you have to answer checks and it's immediate lose if king is mated.

user11215: Appart from the games you can find under https://bit.ly/PreChessGames (translated web for https://www.ajedrezparalaconvivencia.edu.uy/preajedrez) I may add these:
Chess with cards
You may want to try as well chess with cards. You can download the cards and print them.  
Each player has a pile of these cards front face down, and they have to get one card, in each turn, which would tell the player what they have to move. If the player has no valid move with the piece the card states then you may set the rule to move what he/she wants. 
The objective in this game is to eat the king. It’s the only difference to chess rules. And of course you are obliged to move what the card tells you. 
The advantage of this game is that, as there is random involved the kid may win in spite of you playing will all your strenght. 
Obliged to eat
This game is known within some chess platforms as antichess. The added rule is that if any peace can be taken then you are obliged to eat. The king may also be eaten. 
You win the game when there are no more of your pieces in the board or you have no move to make. 

user20694: For kids younger than 6, you could try the following:
Tag/Chase
You start by a specific number of pieces(no pawns or kings) on the board mixed.

One piece is "it" and this piece "chases/attacks" the other pieces. 
All the other pieces try to "run away" from this piece.
If "it" captures a piece, the latter piece is "it"

The players switch when a piece becomes "it", just remember to give a turn to player 2 when switching.
It can be more fun, as the kid has to calculate only 1 piece in relation to the others and it learns to fork and pin pieces. You could add an extra variant later and say the piece has to be undefended.
Tag/Chase without switching sides
A queen is "it" and tries to capture all other pieces, one after the other.
Chess without captures
Captures are not allowed, the goal is to learn how the pieces move.

7002: <p>I'm teaching my 5 year old daughter basic chess. While she's kind of interested, I feel the material, such as how the pieces move, mate in 1 puzzles, basic KQ and KR checkmates, etc, is a bit boring to her.</p>

<p><a href="http://chess.stackexchange.com/a/29017/7002">This answer</a> on another question presented an interesting variant call Rescue Snow White. It combines piece move training with some fun story.</p>

<p>Can someone can suggest other variants similar to Rescue Snow White that motivate children to learn chess? Being fun on the chess board is the main requirement, while the training value is an optional bonus.</p>
 7002: <p><strong>Chess fighters</strong></p>

<p>Idea is taken from the battle chess game. </p>

<p>Play normal chess. When piece A takes piece B, the two players play a street fighter (or whatever fighting game) match. The defender can only move or block for the first 30sec of the match. Whoever loses the match loses the piece. King doesn't fight, automatically wins if taking a piece, but you have to answer checks and it's immediate lose if king is mated.</p>
 11215: <p>Appart from the games you can find under <a href="https://bit.ly/PreChessGames" rel="nofollow noreferrer">https://bit.ly/PreChessGames</a> (translated web for <a href="https://www.ajedrezparalaconvivencia.edu.uy/preajedrez" rel="nofollow noreferrer">https://www.ajedrezparalaconvivencia.edu.uy/preajedrez</a>) I may add these:</p>

<h2>Chess with cards</h2>

<p>You may want to try as well chess with cards. You can <a href="http://www.ajedrezparalaconvivencia.edu.uy/blog/2019/09/06/cartas-de-preajedrez/" rel="nofollow noreferrer">download the cards</a> and print them.  </p>

<p>Each player has a pile of these cards front face down, and they have to get one card, in each turn, which would tell the player what they have to move. If the player has no valid move with the piece the card states then you may set the rule to move what he/she wants. </p>

<p>The objective in this game is to eat the king. It’s the only difference to chess rules. And of course you are obliged to move what the card tells you. </p>

<p>The advantage of this game is that, as there is random involved the kid may win in spite of you playing will all your strenght. </p>

<h2>Obliged to eat</h2>

<p>This game is known within some chess platforms as antichess. The added rule is that if any peace can be taken then you are obliged to eat. The king may also be eaten. </p>

<p>You win the game when there are no more of your pieces in the board or you have no move to make. </p>
 20694: <p>For kids younger than 6, you could try the following:</p>

<h2>Tag/Chase</h2>

<p>You start by a specific number of pieces(no pawns or kings) on the board mixed.</p>

<ul>
<li>One piece is "it" and this piece "chases/attacks" the other pieces. </li>
<li>All the other pieces try to "run away" from this piece.</li>
<li>If "it" captures a piece, the latter piece is "it"</li>
</ul>

<p>The players switch when a piece becomes "it", just remember to give a turn to player 2 when switching.</p>

<p>It can be more fun, as the kid has to calculate only 1 piece in relation to the others and it learns to fork and pin pieces. You could add an extra variant later and say the piece has to be undefended.</p>

<h2>Tag/Chase without switching sides</h2>

<p>A queen is "it" and tries to capture all other pieces, one after the other.</p>

<h2>Chess without captures</h2>

<p>Captures are not allowed, the goal is to learn how the pieces move.</p>
