Toysub!

What's in the box: A rotating set of age-matched educational toys, such as stacking toys, puzzles, pretend-play sets or board games, chosen for your child and swapped on request.

Toysub! is a toy rental subscription rather than a box you keep. After you order, you fill in a questionnaire about your child's development and likes. Staff then plan a set of educational toys and ship it to you. When you want a change, you request an exchange from your account page. A new set arrives, and you send the previous one back. The plans cover roughly newborns to age six. The youngest get rattles, baby gyms and stacking toys, and older kids get puzzles, board games, tool sets and programming toys. The company says every toy is cleaned and sanitized between families. It also says you generally don't have to pay for damage from normal play, and shipping is free. It mentions a joint research project with Professor Makiko Nakamuro's lab at Keio University. The first month is advertised at 900 yen, but the main page doesn't list ongoing plan prices, so check the course page before you sign up. If you want Montessori specifically, note that Toysub! sells itself as a general educational toy service, not a strict Montessori program. Expect a mix that includes tablet-style and sound-making toys as well as simpler materials. The site and service are in Japanese and aimed at families living in Japan.