The fastest checkmates is lesson 1 of 2 in Scholar's mate and quick traps, a tactics course suited to players rated around 680 (beginners). Most quick losses come from the same few patterns. Once you know them, they stop working against you. It has 3 interactive exercises: 3 find-the-move puzzles. You play every move on a board and get feedback straight away. The lesson is free.
What this lesson explains
This is Fool's mate, the fastest checkmate in chess. White moved the f-pawn and the g-pawn, and the diagonal to the king opened. The queen on h4 gives check, and the king has nowhere to go. Early in the game, leave the pawns in front of your king alone.
What you practise
Now you play Black. White has just weakened the king twice. Find the checkmate in one move.
White's queen and bishop both aim at f7. Only your king guards that square, so Qxf7 would be checkmate. This is the start of Scholar's mate. Stop it, and develop a piece if you can.
White's queen has moved for the third time and now aims at f7 from b3. Meanwhile you have developed. Punish it. Find the knight move that hits the queen and also threatens a check that forks the king and the rook.
Worked examples
Now you play Black. White has just weakened the king twice. Find the checkmate in one move. Checkmate in two moves. The king cannot move, and nothing can block or take the queen.
White's queen and bishop both aim at f7. Only your king guards that square, so Qxf7 would be checkmate. This is the start of Scholar's mate. Stop it, and develop a piece if you can. Good. f7 is safe. Nf6 is the best way: it blocks the queen and develops a piece at the same time.
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