Related: 16 essential skills kids learn from LEGO, and fantastic resources to help get them going
Circuit Cubes
A Circuit Cubes set comes with three blocks -- a battery, an LED light, and a motor. When you add these pieces to your LEGO mobiles and connect the circuitry, your cars and tanks and princess carriages are self-propelled by the gear attached to the motor cube. Naturally, this makes your builds a lot more exciting, but what I love most is that these aren't limited to use only with LEGOs. You can create all kinds of cool crafts and DIY projects with them -- from kaleidoscopes to wacky doodling machines. If your kid loves all things STEM, including LEGOs, Circuit Cubes will make a great gift.Flybrix
We discovered Flybrix last fall, and we're still geeking out over the idea that our kids can build their own drones with LEGOs. Then crash them. Then build them again. The price is high for LEGOs, but not that high for drones. And just know upfront that you use an app on your phone to control the drone's flight, so if your kid doesn't have their own device, you'll be getting asked to hand yours over a lot. But you guys, flying LEGOs. How cool is that?Related: What parents need to know about the new LEGO social media app for kids



