Lego Club Jr. It is geared toward younger builders (ages 6 or under).
You can call toll-free 1-866-534-6258 to sign-up for a free 2-year subscription to Lego Club Jr.
Give Operator Code RRJ29
It looks like you are supposed to be able to sign-up online as well, but I tried and I kept being directed to the regular Lego Club Magazine sign-up page. So maybe you can call the number and have the operator sign you up until they correct their website.
Lego Club Jr. Magazine Free Two Year Subscription

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