Bumping - we have found "BanBao" (a chinese lego clone) to be less costly than legos and still a lot of fun.

MagFormers, for the visual types. Beyond expensive, but for us, super-cheap on a cost-per-hour used basis (Grandma built up the collection over a couple years of birthdays and Christmas). Basically, you lay out your figure in 2D magnets, pick it up from the right spot, and voila, a 3D shape. Mr. Spatial loved to torment me - "Mommy, guess what shape this will be!!!". Linear me: "uh.... a rocket?". Him: "Oh Mommy, how can you not see this will be a dodecahedron?"

Looks like all the other magnet building toys out there, but really gets used differently. And still weekly (DS10 and DD7).

The Elenco range (snap circuit guys) includes robotic sets (with and without soldering), a very cool detectolab for forensics kinda stuff, chemical crystal growing kits, microscopes etc.

My favourite combo thus far is a microscope with the USBORNE book on how to use a microscope. fabulous combo gift

Another one is to get different experiment books - start with basic kitchen science and then move on to chemistry. What about building a magnets kit?

I find that it's often in putting these things together that the kids find so much joy!

Try subscribing to superchargedscience.com newsletter - you get some free experiments and links, and special offers for science curriculum dvd's that are quite fabulous - kid watches the video clip, gathers the materials required and does the experiment. They ahve online classes as well that are sometimes offered for free.

We will one day buy their full curriculum, but for now we have enough to go on with our snap circuits, our freebies every now and then, a microscope, dissecting kit and a bunch of science books.

Also check out steve spangler science website.

for engineering - in LEGO look at the WeDo set (intro to robotics and loads of gears, levers, pulley type activities for engineering principles)

There are some places that sell mini construction kits of buildings etc as well.

Not sure if this was mentioned but we have had a great time with good old fashioned paper airplanes (I was lazy and got a book - lots of free designs are floating around the web).

Anyway we had a lot of fun making (folding?) it and now it's DS4's favorite toy (for now).

We are big into origami at the moment.

I just got my DD a soldering kit and a Make Raspberry Pi kit for Christmas from Radio Shack this afternoon. She will need some parental guidance and supervision (safety will be a paramount concern) to start with but she has been making some pretty intricate Rainbow Loom designs over the past couple of years so I think she now has the dexterity required.

She will be starting the AoPS Intro to Python class next February so putting a computer together from components and learning to program ought to give her a solid footing. If she takes to this we will try some Arduino boards. I'll let you all now how it goes...

My little guy is exactly the same! Loves taking things apart and putting them back together - but oy what a mess that can make! (I saw someone mentioned an incident with a Roomba.. agh!) Our new favorite toy (yes, OUR favorite, because it keeps his attention without creating a mess ) is this thing called a Vertical Vortex, which is basically like a flow toy that's perpetually in motion.. it basically disassembles and reassembles itself so long as he keeps it moving! Good way to teach kinetics to a young'un, while also being a little artsy as well lol

A few updates on this thread from age 8-9:

Turing tumble - marble based mazes / logic puzzles
https://www.turingtumble.com/

Rush hour game - logic based puzzles
https://www.thinkfun.com/products/rush-hour/

Tinker crates You'll want to pick through these, as some topics are far better than others, but DS enjoyed some of the Tinker crates around age 7-8:
https://www.kiwico.com/tinker?utm_source...hhoCMzAQAvD_BwE

Foldscope - a portable, virtually indestructible pocket microscope
https://www.foldscope.com/

Terrific field guides for biology - because books ARE games and toys in our household...

Mycology / foraging:

• Roger Phillips - "Mushrooms and Other Fungi of North America"
• Gary Lincoff - "National Audobon Society Field Guide to North American Mushrooms"
• Kikkerland - Foragers Playing Cards

Entomology:

• Joseph Wilson & Olivia Carril - "The Bees in Your Backyard"

Lego power systems design books

• Yoshihito Isogawa - "The Lego Power Functions Idea Book - Machines and Mechanisms"
• Yoshihito Isogawa - "The Lego Power Functions Idea Book - Cars and Contraptions"

Great digital resources we've used - a motley mix of YouTube(YT) and other resources

• King of Random (YT)- https://www.youtube.com/user/01032010814
• SciShow Psych (YT) - https://www.youtube.com/c/SciShowPsych
• Neuro Transmissions (YT) - https://www.youtube.com/user/neurotransmissions
• Physics Girl (YT) - https://www.youtube.com/user/physicswoman
• Veritasium (YT) - https://www.youtube.com/user/1veritasium
• Phet @ UColorado - https://phet.colorado.edu/
• Praxilabs - https://praxilabs.com/en/virtual-labs
• Science Buddies - https://www.sciencebuddies.org/
• Can't recall all of the sims we've used, but we pick through these virtual labs (definitely check out "Open Neuroscience Education"- a bit advanced, but drives engagement for DS; "Build Your Own Brain", and "Royal Society of Chemistry") - https://libguides.mines.edu/oer/simulationslabs
• CodeMonkey (for basic coding) - https://app.codemonkey.com/
• Planet Maker - http://planetmaker.apoapsys.com/
• BioMan - https://biomanbio.com/

...whew! I'll drop back in with edits if I can think of more go-tos. As you can see, the pandemic has treated us well wrt science play.

I have looked into Turing Tumble based on aquinas's suggestion

It is a bit pricy at $70+shipping but it's certainly quite unique.

Has anyone tried it out and would be willing to share?

Thanks