Toys that teach - nesting blocks

I rarely write about toys, because they don't take a lot of space in our daughter's life. Of course, space in our house is another matter. She strongly prefers books and outside activities at this point, and we prefer it this way. When we pick toys for her, we try to avoid toys with batteries, where pressing the button leads to a predictable (and eventually boring) result. She has a lot of basic Duplo blocks and other building toys. For the past week or so her favorite toy was this set of nesting blocks that we got about a year ago from my parents. My mom has this interesting tendency to pick good toys, but give them to her beloved granddaughter about a year too early. Unfortunately, I couldn't find the link on the web for this particular set, which I find the best from what I've seen. I like it, because it's so versatile. It's a nesting toy (Anna still can't concentrate long enough to nest the blocks back together), a stacking toy, and also a puzzle which requires to turn the blocks in a certain way to arrive to a proper picture on each side. Each side represents seasons of the year - another "teaching through play" moment. Anna gets better and better at assembling this tower by herself. Here is our exchange while she was at it:

Anna: This is a spring boy, mama. Why is it raining?

Me: It rains often in the spring.

Anna: It's spring now. And it's not raining.

Me: Well, our spring comes earlier. Remember, it rained a lot a few weeks back? And it rains a lot now in the other parts of our country.

Anna: Yes, when we went to U&R (our neighbors) and brought them cake, it was raining. Then it was spring!