Problem of the Week

Elementary checkmates

Several years ago, I developed the habit of posting a portion of each week's chess lessons for youth players on Chess Skills. These were labeled with "Problem of the Week". After a few years, I stopped doing these posts weekly, but would post one from time to time. I seem to be slipping back towards the regular habit.

My students this week in the after school club were presented with some checkmate positions.

On Tuesday I presented the first ten moves of a game that I played online the day prior, then asked students to work out the forced checkmate in five. Although the position differs slightly, the five move sequence is identical to one found in Vladimir Vukovic, The Art of Attack in Chess (1965).

Stripes,J. -- Internet Opponent [C10]
Live Chess Chess.com, 17.10.2022

1.e4 e6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nf6 5.Bd3 Nxe4

5...Nbd7 has been my choice with Black.

6.Bxe4 Bd6

Both 6...c5 and 6...Nd7 are better.

7.Nf3 0-0 8.Bxh7+?

In this instance, the classic bishop sacrifice leads only to equality with best play.

8...Kxh7 9.Ng5+

Black to move

9...Kg8??

9...Kg6 was necessary 10.h4 Kf6 is best 11.Nh7+ Ke7 12.Nxf8 Kxf8 is best with equality.

10.Qh5+- Re8

Moves into forced checkmate

Black's woes are illustrated by the computer's suggested alternatives:
10...Bb4+ 11.c3; or
10...Qxg5 11.Bxg5

White to move

On Thursday, I first presented a situation that led to a draw in the previous Saturday's youth tournament. After more than a dozen moves, a young player with rook and knight against a lone king admitted inability to force checkmate. I asked a few students to show how they would find checkmate from this position.

White to move

After students showed their methods, I reviewed the process of keeping the Black king in an ever shrinking box. Then I presented a common exercise that Bruce Pandolfini has in his Pandolfini's Endgame Course (1988), 27.

White to move

Any rook move begins the process of delivering checkmate by force in three moves.

White has a mate in three with the rook on any square marked in yellow.

The real challenge was in solving a puzzle that dates from the mid-fifteenth century (before the bishop and queen gained the power they have now). 

White to move

Checkmate must be delivered in 12 moves or less. The rook can only move once was a stipulation of the problem. This problem shows that chess players know how to use opposition and outflanking more than 570 ago.