Quick answer
Quick answer: Start with pawns only, then add one piece at a time. Let them win the early games. Stop each session while they still want more. Full games with all the pieces come last, not first.
The usual approach is to explain all six pieces in one sitting, and it's why so many children never play a second game.
I read through the standard teaching order before writing this. The rules themselves are set out on the rules of chess page, and the order you teach them in matters more than the rules do.
Why the full board fails
Thirty two pieces and six different movement rules is a lot to hold at once.
A child who's still working out how a knight moves cannot also plan, watch for threats and remember whose turn it is.
So the first game becomes a memory test rather than a game, and memory tests aren't fun.
Strip it back. A smaller board with fewer pieces is a real game, and a real game is what makes them ask to play again.
Start with pawns only
Set up just the eight pawns each and the two kings. Nothing else.
The goal is simple. Get a pawn to the other side, or take all of theirs.
One movement rule, one capture rule, and a clear target. Most children get this in about two minutes and then play happily for twenty.
It also teaches the thing that actually matters later, which is that pawns capture differently from how they move.
Add the rook next
Rooks move in straight lines and children find them the easiest piece to picture.
Play pawns plus one rook each for a few games. The rook suddenly makes threats real, and they start seeing squares rather than pieces.
Then add the second rook. Then the bishop, which is the same idea turned diagonally.
By the time they've played with all four, half the board makes sense and nobody has explained anything twice.
The knight goes last for a reason
It's the hardest piece and it breaks the pattern the others share.
So introduce it after they're comfortable with everything that moves in a line, and teach it as a shape rather than as a rule.
Two squares then one, and the landing square is always the opposite color. That last part is the tip that makes it click.
A good drill is putting a knight on an empty board and having them touch every square it can reach.
Let them win, and be honest about it
A beginner who never wins stops playing. That's not a chess problem, it's every game.
So lose deliberately in the early sessions. Not obviously, and not every time. Just often enough that winning feels possible.
As they improve, take back a piece of your handicap rather than suddenly playing properly.
The day they beat you when you were trying is the day they own the game, and it should arrive gradually.
Stop before they want to stop
This is the single best piece of advice on the list and it's the hardest to follow.
End the session while they're still enjoying it. Twenty good minutes beats an hour that ends in frustration, every time.
A child who finishes wanting one more game comes back. A child who finishes tired and beaten doesn't.
So watch their attention rather than the clock, and put the board away early.
Teach checkmate before you teach openings
Children want to win, and winning means checkmate, so start there.
Show the simplest finishes with a queen and a king against a lone king. Let them do it themselves twenty times.
That gives them a goal to aim at, which turns aimless moves into a plan.
Opening principles can wait. Our beginner openings guide is worth reading when they start asking why the first moves matter.
Stalemate needs explaining early
Nothing frustrates a child more than winning everything and then drawing.
So explain stalemate the first time it nearly happens, at the board, with the position in front of them.
The rule makes no intuitive sense until you've seen it cost you a game, and then it makes perfect sense forever.
Our explainer on stalemate against checkmate covers the distinction in the words to use.
Never take a move back for them
This one feels kind and it teaches the wrong lesson.
If a piece can be rescued after the fact, nothing is at stake, and nothing being at stake is why the moves stop mattering.
So let the mistake stand and let the game go on. A lost queen is a memorable teacher and children recover from it in about a minute.
What you can do instead is offer a hint before they move, once per game, which keeps the stakes real.
Name the pieces properly from day one
Horse, castle and pointy hat are easy to say and they cost you later.
A child who says knight, rook and bishop can read any book, watch any video and join any club without relearning the words.
It costs nothing extra to use the real names from the first session, and children pick them up without noticing.
The same goes for check and checkmate. Say the words every time, and the meanings settle in on their own.
Do not correct every move
The instinct is to point out each mistake as it happens. Resist it.
A child who is interrupted every move stops thinking for themselves and starts waiting to be told.
Pick one thing per game. Just one. Mention it afterwards, not during.
They'll improve faster on one lesson they absorbed than on ten they nodded through.
Play on a real board first
Screens are fine later. A physical board is much better at the start.
Pieces you can pick up teach the shape of the game in a way a screen doesn't, and there's no timer, no rating and nothing to lose.
It's also easier to point at squares with a finger than with a cursor.
Move to a screen once they know the rules, because that's where the practice partners are. Our board works with no account and no clock.
Puzzles work better than games
Once the rules are in, simple tactics puzzles are the fastest way to improve, and children like them more than adults expect.
A puzzle has one right answer and immediate feedback, which is exactly the shape a young learner wants.
Start with one move mates and captures, not with anything clever.
Our guide to forks, pins and skewers covers the three patterns that come up first.
What age can they start
Earlier than most people think, if you use the reduced setup.
A four or five year old can play the pawns only game happily. The full game usually clicks somewhere around six or seven, and later is completely normal.
Pushing a child who isn't ready is the main way chess gets ruined for them.
If they lose interest, put it away for six months. It comes back, and it comes back stronger.
The draw rules will confuse them
Repetition, the fifty move rule and insufficient material all feel unfair to a child who was winning.
So teach them as they come up rather than in advance, and explain the reason behind each one.
A rule with a reason is remembered. A rule read from a list isn't.
Our summary of the five ways a game can be drawn is the version to have to hand when it happens.
What to do when they get better than you
It happens faster than you expect, and it's the point.
When it does, stop trying to teach and start playing properly. They need a real opponent more than they need a coach at that stage.
A club is the next step, and it's worth finding one earlier than feels necessary.
I watched this happen with a nephew inside four months, which is faster than any adult beginner I have taught.