Stanford Puzzles 4 and 5
I felt I solved Puzzle #5 a little slowly, but it has a narrow solving path and I wasn't seeing the necessary point when I solved it. It is very good practice for "pointing pairs" which make natural sense with my note system anyway.
Puzzle #4 - by Wei-Hwa Huang
Solution of Puzzle #4 - 1 minute, 43 seconds
Puzzle #4 explanation
Puzzle #5 - by Wei-Hwa Huang
Solution of Puzzle #5 - 3 minutes, 10 seconds
Puzzle #5 explanation