Opening
A First Junior Chess Opening Repertoire -- PDF -- PGN
The French Defence in 10 minutes PDF
DJCA Videos -- Scotch Game -- Two Knights' -- White with 1.e4 -- Black vs 1.e4 -- White with 1.d4 -- Karlsbad -- Black vs. 1.d4
Your First Chess Adventures -- openings booklets in PGN and PDF -- link available on request -- Colle System
YouTube videos for all DJCA booklets from DJCA and others
Inspiration -- Semi-Slav -- Schliemann -- QG -- Karlsbad -- IQP Example -- King's Indian
Planless development -- SB38
Tactics
A course in chess tactics -- PDF -- PGN -- video playlist
Defending (video)
HitMissTrap 1 & 2: Q1 Q2 A1 A2
Paul's Puzzles
Test Your Chess IQ 1 2 3
Strategy
The positional elements - a list
Evaluation (sample PDF) Chess Exam
Planning (video)
Test Positions: MS99 -- BK39 -- BS38 --
Silman Thinking Technique -- PDF
Can You Be A Positional Chess Genius (Test 1 -- Hints -- Answers)
Endgame
Endgame puzzles at Lichess
Littlewood's ABC -- Lichess studies -- PGN
Capablanca's Best Chess Endgames -- Lichess studies -- PGN
Icelandic Endgame Challenge -- PDF -- PGN
Daniel's Endgame - Lichess
Thinking
8 Queens (Lichess)
Checks and Captures (Lichess Study)
Boardsight exercises (from Chess Deck)
Visualisation KKMG1 -- KKEG -- KKMG2
Think Twice -- T21 -- T22 -- Saariluoma -- PDF
Blunder-Proofing Your Chess (video)
Do chessplayers think? record yourself thinking (Lichess)
Thinking (video)
Misc
Chess Choice Challenge 1 2 3 (Q only)
It's Your Move / IYM Improvers / IYM Tough Puzzles (Q only)
Chess Exam -- PDF Q only