I have so many favourites!  I love that these puzzles cover so many different areas; maths, geography, culture, biology! When choosing puzzles for my children I consider each child's skill level and interests and I think about which puzzles we already have at home. Otis is currently using puzzles 2 and 7. I think that he will use 1 in the next couple of months. I'm thinking of getting 4 and 8 for his birthday. I have one more puzzle post to come featuring (and perhaps explaining) puzzles you might find in a Montessori school.