So you'd like to buy a robot?

If you'd like to have a robot at home, and you'd like that robot to be somewhere within the LEGO product universe, what should you buy?  You have three (in-production) options:  BOOST, WeDo 2.0, and EV3.

Of course, if you're joining or starting a FIRST team, what robot you use will be already determined for you by the type of team.  FLL uses EV3 (or NXT), while FLL Jr uses WeDo (1.0 or 2.0).  Currently, BOOST is not legal for any FIRST competition.


EV3 is the "big kid" product, nominally for ages 10+.  It comes ready to program with the EV3-g graphical programming language, which includes data-logging, advanced math, and other features that can be used to do some serious programming.  (Blocks can be seen here, but many blocks have multiple modes.)
Education set.

EV3 is technic-based.  There are no studs here, just pins and axles and liftarms.  This can be a new experience for LEGO builders who've only done System (studs and bricks) builds.

The parts included in the kit are enough to build a basic robot driving base with multiple sensors, with a motor leftover for doing something interesting, such as picking up an object.  If you want a fourth motor, you can buy one separately.

There are two different EV3 releases available:  31313 is the Home version and has an IR sensor and remote (which are not allowed for FLL).  45544 is the Education version and includes an ultrasonic sensor and gyro sensor.  The Education version also includes a rechargeable battery.  Both have three motors (two large, one medium).  Both use identical intelligent bricks.  Both can be programmed either the home or education version of the software (both of which are free).   There is also an expansion set, which has more Technic parts and directions for additional builds when combined with the education set.  It contains no motors or other electronics, and whether it is a good value depends on whether you happen to want the parts it contains.

If you think there's a chance your EV3 will become an FLL robot, or you want the battery or the gyro sensor, it makes sense to buy the Education version, which you'll find on the LEGO Education website, but not in regular Shop@Home.  There's an excellent comparison of these EV3 options at RobotSquare.  There's a pretty big trade in EV3 sets (mostly home, but some education) on eBay and other sites.  Be warned that sellers may not have bothered to do an inventory of what parts are present, so while there are deals to be had, there are also disappointments.
Home set

The EV3 can be programmed with a computer (PC or Mac) over Bluetooth or by plugging in a USB cable.  You can write programs without being connected to the intelligent brick, and then transfer them later.  The software also includes tutorials (with a different selection for Home vs Education software).

The EV3 can also be programmed with the tablet app (which runs on iOS and Android tablets, but not phones) or a Chromebook, but the tablet/Chromebook app is significantly limited compared to the computer.  The app will only suffice for novice programming.

Update, January 2020:  The original EV3 software (sometimes called EV3-g) no longer runs on recent (Catalina) versions of MacOS.  A new scratch-based programming language has been released for Macs, and a version for tablets/Chromebooks/Windows is promised for later in 2020.

When you're tired of dragging data wires around in EV3-g, the brick can be easily booted into Linux with a microSD card with an ev3dev image, allowing you to program it in any number of textual programming languages.  (This is not legal for FLL, however.)  Booting Linux is fairly straightforward, and since you load the operating system from the SD card, you can go right back to your brick being a vanilla EV3 by just removing the card.  Update 2019:  There's now a Python version for EV3 released by Lego Education, in addition to ev3dev.

What'll it cost?  List prices (US) are $349 for Home and $412 for Education.  The expansion set is $105 directly from LEGO Education.  You can find the Home set at MSRP (rarely below) from a variety of etailers, including Amazon (affiliate link).  Education sets are often offered for sale on marketplace sites at above MSRP, sometimes by a substantial margin.  Buy direct from Lego Education instead, but expect to pay shipping (about $8 per set).  Used sets appear frequently on eBay, with complete-ish Home sets running about $200-250 and education sets running $300 and up.

There is a modest discount available to registered FLL teams, so if you're affiliated with a team, it'll make sense to buy through the team if possible.  (If you're starting a new FLL team, register the team before buying from LEGO Education, if possible.  Registration opens in May.)

For more parts, eBay or Bricklink are good options.

WeDo 2.0

The WeDo 2.0 is the current Lego Education product for elementary school kids.  The projects are simple, easily built in a class period.  The bricks are a mix of Technic and System.

The WeDo 2.0 is controlled from a tablet (iOS or Android) or computer over Bluetooth.  The program runs on the tablet or computer, not on the WeDo2.  Unlike the EV3, where the programs are copied to the intelligent brick, where they stay forever, the WeDo intelligent brick does not store programs or do anything independent of the tablet/computer.  This isn't a problem really, just a difference to be aware of.

NOTE: LEGO doesn't officially support the WeDo app on Kindle, and you won't find the app in the Kindle store.  However, if you install the Google Play store per these directions, the Android app works just fine.  (As of 4/2018, confirmed for 2017 HD7 and HD8 Kindle Fires. As of 1/20, also good with 2019 HD8 Fires.)

The WeDo's biggest limitation is the number of ports.  It has two.  That means you can have two motors (if you buy an extra one separate from the basic kit) or a motor and a sensor, or two sensors.  Since a basic robot driving base requires two motors, a basic driving base has no ports leftover for a sensor.  This is a significant limitation.

I love the basic, small builds included in the WeDo directions, and I love the projects included in the software.  My five year old can sit down and build one of these in one sitting.  But I would love the WeDo a lot more if my kids could build a robot that could easily drive around the house avoiding obstacles.

The WeDo app includes both directed building with exact directions and projects that challenge kids to improve upon an existing build or to design and build something of their own.  It's great stuff.

The native programming language is a graphical programming language, not too different from EV3-g.  It is possible to do somewhat sophisticated programming with it, but it the entry-level programming is simpler than EV3-g.  You can see the blocks available at LEGO's website.

What'll it cost?  List price (US) is $189.  WeDo 2.0 is new enough that there aren't many used sets out there yet, and direct from Lego Education seems to be the only (reasonable) option.  (Sets on Amazon are marked up above MSRP.)

There is a modest discount available to registered FLL Jr teams, so if you're affiliated with a team, it'll make sense to buy through the team if possible.  (If you're starting a new FLL Jr team, register the team before buying from LEGO Education, if possible.)


BOOST is the second-newest member of the LEGO robot family.  This is a consumer-targeted set, with more play features than WeDo.  Unlike WeDo 2.0, it can be bought from any number of retailers, and sometimes can be found on sale.  The listed age range is 7-12, but older kids and adults may also enjoy it.

Like WeDo 2.0, BOOST communicates with a dedicated tablet or Windows 10 laptop (with compatible Bluetooth), and does not run independently.  The list of user-confirmed compatible devices is longer than LEGO's official list:  Android (including Kindles), iOS.

BOOST is predominantly System (brick) based, with a few technic parts in the mix.  Unlike WeDo 2.0, the builds are extensive, and will be challenging for a novice LEGO builder.  There's some scaffolding and stop and play built in, which helps somewhat.  There are a lot more parts in the BOOST box than in a WeDo 2.0 box, although WeDo 2.0 gives you a nice plastic bin to sort them in, while BOOST comes in a cardboard box.

While the WeDo 2.0 comes with one motor, the BOOST has three.  Two separately-controllable motors are present in the "move hub", which makes programming a driving base robot very easy, and indeed a driving base is the first introductory build.  There's also another motor which can be connected to one of two available ports.  There is significantly more functionality here than with the WeDo.

Like EV3 and WeDo, BOOST uses a graphical coding language.  The coding blocks available are extensive, although the scripted early builds only unlock a few blocks at a time, so kids aren't overwhelmed.  Like WeDo, you can't play around with the programming palette unless the tablet is paired with the BOOST, which can occasionally be a nuisance.

The BOOST is arguably a younger kid's toy, but there's enough going on with the programming that older kids and adults may also enjoy playing with it.  As more builders get it, we're likely to enjoy more user-released directions, such as these from JK Brickworks.

The LEGO BOOST Idea Book is a good addition to the app, and focuses more teaching how to build fundamental mechanisms rather than large robots to play with.

What'll it cost?  List price is $159, but sales happen.  You can buy from any major etailer (such as Amazon - affiliate link) or direct from Lego Shop@Home.

What should you buy?

For younger kids, it's a real toss-up.  WeDo builds are so much simpler that they may be the best option for younger builders with short attention spans.  But if you want a robot cruising around the floor and responding to its environment, you'll need a BOOST.  The BOOST is the lowest entry cost, and much better for building robots that drive, but the builds included are complex, and there's much more focus on playing with the robot, not learning with the robot.  Both are fun and educational, but the emphasis is different.  

I really wish LEGO offered small projects like the ones in the WeDo, but with a move hub like the BOOST.  That I'd buy and recommend in a heartbeat.

For older kids (about 10+), either EV3 or BOOST offers a lot of value.  If you aren't sure if your child will be excited about robotics, starting with a BOOST is a reasonable option, and offers a great deal of play value.

For another take on the WeDo vs Boost question, visit Robocamp.
And here is Lego's own comparison of Boost vs Wedo

New for 2020:  SPIKE Prime

SPIKE Prime is the newest robot addition.  It should be FLL-legal for 2020-2021 (based on it being intended to be legal for 2019-2020 before a production delay meant it didn't release on time).  The programming language is scratch-based, similar to the new EV3 Classroom, but at this writing (January 2020) it doesn't appear that the SPIKE app can control the EV3 or the EV3 app can control the SPIKE, despite language similarities.
LEGO has said that SPIKE Prime doesn't replace the EV3, and it appears to sit in the gap between WeDo and EV3, with a slightly easier building system than the EV3, but much more functionality than the WeDo.

Bonus content: NXT (not in production)

The predecessor to EV3 was NXT.  If you come upon one at a garage sale at a good price (or shake down a college-aged kid for the one in his/her closet), you can program it with the EV3 programming software, or the original NXT-g programming software.  The NXT has some limitations compared to EV3 (not as easy to use a different programming language, no Bluetooth support in EV3-g, one less motor port), but if you happen on one cheap, grab it!  The motors and most sensors will work on an EV3, and useful Technic parts are useful Technic parts, regardless of color.

Caution:  The NXTs can have issues with the screen malfunctioning, and many have come out of closets with intelligent bricks destroyed by battery acid.  Inspect carefully.  While LEGO sometimes does replace malfunctioning NXT bricks (STILL!), don't spend so much that you'll be unhappy if your intelligent brick fails.

In 2019-2020, NXTs were still legal for FLL.  A cheap NXT could be a good secondary robot, but I hesitate to recommend it as a primary robot, due to the possibility of screen failure mid-competition.