Amazon is launching a new STEM Club subscription service for monthly, STEM-related toys. For $19.99 a month (plus tax), Amazon will deliver a “hand selected” educational toy that will theoretically both entertain and educate a child in the fields of science, technology, engineering, and math.

The subscription is split up into three different versions: one for children aged 3–4 years old, one for those aged 5–7 years old, and one for 8–13 year olds. Once signed up, the toys — which TechCrunch notes will come from recently launched or Amazon exclusive products — will arrive each month as an automatically renewing monthly subscription, similar to Amazon’s automatic Subscribe & Save service.

It’s a savvy move for Amazon which has had a STEM toy-focused storefront on its online store since 2015. The subscription service is another step forward in pushing science and technology playthings to parents looking for more educational toys, while simultaneously adding more recurring monthly services for Amazon customers. Amazon is currently only launching a STEM Club toy subscription for now, but it’s easy to imagine that other toy subscriptions could follow if the STEM service is successful.

Hopefully, with all these toys arriving every month, Amazon will also be selling some kind of infinitely large toy closet to store them all, too.