Compared to Japanese school summer vacations, the summer vacations doled out by English and American schools are heaven. The Japanese school year goes from April to March, and summer vacation occurs during, rather than at the end of, that school year.
Therefore, the summer vacation period tends to be almost worse than the school terms for Japanese kids. Even kindergarten kids get assigned homework. Older kids often go to cram school to prepare for entrance exams that loom in February. When I was 15, I spent the whole, rainy summer commuting 90 minutes round trip to a drab cram school in Shinjuku. That was the year that my little sister Meg got so sick that she was hospitalized for a month, with my mother at her side. My other sister Mayumi was sent away to my grandmother's, and I had to spend the whole summer with my father. I didn't get along with my father in my teens.
Those memories of anxiety and stress filled summers growing up have made me want to do as little as possible during the warm months in my adulthood. Actually, in the springtime I always have big plans for what I'll do - learn a new skill, or finally clean up and design the garden, or take some sort of seminar. It never happens though. (The one summer I actually signed up for a seminar back in college, I rebelled against my own plans and took off for a couple months to Europe with a backpack.) My garden usually suffers because of this, which bothers me when I survey the mess in the fall. But ultimately I don't see that it matters that much. The garden still fills up with beautiful flowers, the birds are happy to find so many slugs to feed on, and the strong, wild old roses bloom regardless.
Busy, stress-filled summers filled with preplanned activities sap away energy and dreams. Don't do that to your children, or they may grow up to be slothful adults.