My grandson wants a LEGO Power Motor to use with his gigantic box of Lego pieces. He is 11 years old and seems to know his way around the world of LEGO bricks. I, though, haven't a clue what he is asking for. I see things such as "EV3, NXT, RCX, and NXT-G and I'm confused. Can anyone help me? What is it I'm looking for?
You say he is looking for a "Power Motor", which sounds like he is referring to the LEGO Power Functions line. The bare minimum you need to get a spinning motor would be one of the battery boxes and one of the motors.
The terms you listed however refer to the different generation of Mindstorms robotics.
- EV3: Current generation
- NXT: Previous generation
- RCX: First generation (rather old and difficult to use with modern computers)
- NXT-G: The GUI used to program the NXT robots.
Mindstorms do include motors, among other things, but are mainly geared towards use with robotics.
While Alexander's answer is completely correct, I wanted to provide an alternative that may work a little better while being a bit more expensive. Buying a motor and battery box is certainly the cheapest way to get a spinning motor, but depending on your grandson's collection, this might not provide the best experience.
In order to build creations that operate using motors, it is helpful to have the following in addition to a battery box and motor:
- Wheels that fit axles (the majority of wheels in the LEGO system are not designed to be driven by a motor)
These pieces form what is commonly branded "Technic", though they are found in non-Technic sets which sometimes feature moving parts.
It can also be helpful to see how motors are used within the larger LEGO system. The best way to get all the needed components and see them in action is to buy a complete set that is motorized. For example:
This set contains loads of axles, wheels, and gears, which together provide a great base for mechanical building. Sets like this are typically expensive ($150+), but could be worth it you depending on your means.
Also, to directly respond to your confusion over the many acronyms, the current manually controlled motor system is called Power Functions (see the logo on the above box). Everything else (EV3, NXT, RCX, etc) is related to robotic and computer controlled motors.
If your grandson has lots of Technic pieces, such as gear wheels, axles, beams with holes etc (if he knows his way around Lego he should be able to confirm that pretty easily), the Lego have a good starter set which contains a motor, battery box and a few other pieces. It's how I started updating my old LEGO Technic sets from the early 90s to be motorised and eventually radio controlled.