Legos are going green.

https://www.theverge.com/2018/3/2/17070454/lego-bricks-sustainable-plastic-toys

They are starting to use a new materials to make the bricks so that they will be green. The plan is to achieve fully green products by 2030. So go Legos.

Moose turds from tirdy works

https://youtu.be/CsROq2VKlYE

Legos are very green - last forever and can be passed along.

Yes. To all of this. Buy some vintage lego and get a few vintage Erector sets as well (the good ones with the little motors.) Also, maybe a bottle or two of wine for yourself, it'll be ok.

Buy them second hand at a yard sale.

If you live in a friendly neighborhood, make a request to the neighborhood email group. In my NOVA neighborhood, you'd probably have as many as you need within 24 hours.

There is no way that cutting down trees to make wooden blocks that will be played with for a brief period is nore environmentally friendly than buying used legos and donating or reselling them when you are done.
My kid are also using legos from the '80s, along with their new ones.

Because you compost all of your other toys when you are done with them?

Here's what you do: buy or build your own colonial brick molds of various sizes:

https://www.sevencolonial.com/shop/more/vintage-more/indus-brick-mold-open-homart/?gclid=EAIaIQobChMI15OQzcHV4AIVRlYNCh3TywrZEAQYAyABEgKcOfD_BwE

Then, teach your child how to mix adobe, and create and dry your own lego-ish brickletts. https://www.heifer.org/join-the-conversation/blog/2018/October/how-to-make-mud-bricks-and-why-you-might-want-to.html

You can use one lego as a model to create the needed bumps and dents.

Hours of fun!

My husband is in his 40s. Our kids have his legos and they have a while bunch of classic books from me. If you want green buy used! Also stop buying your kid those 200US Boden outfits that end up in landfills. Buy used and resell. That is the best way to be green.

If you just want to be holier than thou about plastic toys, then you won!

We got a used set that my parents picked up from Goodwill. I don't think brand new wood blocks are greener than that. My kids love them.

Buy them used. Especially duplos. I got a ton of sets for 10-20 each and will sell/pass on when dd is done. We still have my husbands sets from 30 years ago. That's pretty green if you ask me.

In today’s world of cheap and bad plastic toys real LEGO is probably one of the last remaining real quality bastions. The way the company manufactures them (and Duplo as well) they don’t fade, don’t age and always have that perfect “clic”. They will last for decades and will be always like new. That is precisely why they are so expensive compared to all the other toys out there. There are many other companies that try to imitate Lego’s success - and they simply can’t. Their stuff is indeed cheap plastic crap (as anyone who tried to build anything with “imitation legos” can attest to).

You could always whittle your own blocks OP. Then when your child is old enough, you can teach him woodworking. It’s a good skill to learn. The nice thing is, you’ll be able to make toys besides “legos.” https://www.amazon.com/Chipping-Away-Beginner-Wood-Carving/dp/B01JAUUTOC/ref=asc_df_B01JAUUTOC/?tag=hyprod-20&linkCode=df0&hvadid=309807964063&hvpos=1o1&hvnetw=g&hvrand=12988935998855419961&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=9032001&hvtargid=pla-493685707148&psc=1

I just got them on eBay. Some sellers will do by weight.