National Geographic Little Kids -- complete with tear-out animal cards in every issue-- tops our list. Inside is also a fun science activity (that's where we learned about dancing raisins), It is simple, has zero ads or commercial tie-ins like its big kid version.
It's been a while, but I think I can come up with more.
Zootles
My Backyard
Both are animal magazines.
Baby Bug--by the folks that publish Spider and Cricket. This glossy, durable little magazine was a favorite in our house through the age of 5, when they started discovering other magazines.
Ladybug-- the next age group up by the same publisher, and if he's a precocious reader, might be on his level, but otherwise has a lot of engaging poems and stories you can read together.
I would hightail it to your area libraries, and check out their offerings before committing to a subscription. However, that little Nat'l Geo is a sure pleaser, I think, and inexpensive. I vaguely remember a couple more. I'll post if I remember them.
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