Colle-Koltanowski: the e4 break is variation 1 of 6 in the Colle System course, a beginner opening course for White (ECO D05). It runs 24 moves and begins 1. d4 d5 2. Nf3 Nf6 3. e3 e6 4. Bd3 c5 …. The classic Colle. White builds the triangle, takes on c5 and pushes the pawn to e4. The centre opens, and White's pieces get free play toward Black's king. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. d4 – White takes the centre with the queen's pawn.
1... d5 – Black meets it in the centre.
2. Nf3 – The knight develops and guards d4 and e5.
2... Nf6 – Black develops too.
3. e3 – The Colle move. It opens the f1 bishop and keeps d4 solid.
3... e6 – Black opens the way for the dark bishop.
4. Bd3 – The bishop goes to d3 and aims at h7.
4... c5 – Black hits d4 from the side.
5. c3 – The Colle triangle. The pawns on c3, d4 and e3 hold the centre, and White prepares the push to e4.
5... Nc6 – Black adds pressure on d4.
6. Nbd2 – The knight goes to d2 to support the e4 push.
6... Bd6 – Black's bishop aims at h2 and stops the e5 square.
7. O-O – White castles.
7... O-O – Black castles too.
8. dxc5 – White takes first. Black's bishop must spend a move to take back, and the e4 push gains force.
8... Bxc5 – Black takes back with the bishop.
The lesson goes on for 8 more moves, each with its explanation.
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