As AFOLs, there’s a lot we take for granted when it comes to knowledge about LEGO. Recently, while helping my son with a build, he asked me what one of the printed symbols meant in the instructions, and I realized just how many symbols there can be in one LEGO instruction booklet. When newcomers or children come into the hobby, it can be confusing to figure out what all this means.

Below, I’ve gathered 12 symbols from LEGO instructions that I could find in current use and written what they mean. I was also curious about how well they translate, so I assembled an impartial panel to scientifically measure the symbols’ effectiveness. And by scientific panel, I of course, mean I asked my three boys, aged 3, 5, and 7, what they thought the symbols meant.

Symbol 1 - Simultaneous Builders

LEGO has recognized that people like to build together, so some sets will provide multiple instruction booklets that correspond to, for example, different floors of a building or mini-builds, eliminating the need to take turns. This symbol lets you know how many people can build at the same time. As a newer symbol that we haven’t seen very much, it was a challenge for our panel.

Kids’ Guesses:

3yo: You need one four, one and four
5yo: 1 to 4 people can eat candy!
7yo: One to four people can play the game.

Symbol 2 - Digital Instructions QR Code

An experienced adult could reasonably deduce that by scanning this QR code with a smartphone, you’ll be taken to a link where you can get the instructions in the LEGO Builder app (and now also register the set for those sweet LEGO Insiders points). Maybe it’s a testament to how ingrained cellphones are in our life, but the panel did better with this one than I would have expected.

Kids’ Guesses:

3yo: Use your phone to scan the picture.
5yo: I have absolutely no idea and I don’t want to know. Something about phones.
7yo: If you scan the code with your phone, it’ll show you the instructions on your phone.

Symbol 3 - Building Guidance

This isn’t so much a symbol as it is a mini-comic, with the recommended building steps and instructions on using the brick separator as well as another QR code with a link to a video. I was curious to see if the large volume of information on this page would translate, but it seems like our panel mostly got the jist of it.

Kids’ Guesses:

3yo: It means you need LEGOs, it has LEGOs and you need them if you want LEGOs.
5yo: Oh! I know this one, the brick separator can break off bricks from other bricks so it’s showing you that.
7yo: This shows you that there are going to be multiple numbered bags, and then you build them in order. Also, the bottom shows you how to use a brick separator.

Symbol 4 - Piece Not In Bag

This symbol lets you know that a piece that you’re looking for is not in the numbered bag, it’s packaged separately. Without context, I think this symbol is pretty confusing and definitely threw the panel for a loop. I’ve heard that this symbol was created in preparation for when the numbered bags move from see-through plastic to the opaque paper bags that LEGO will be moving to in the future, but I haven’t found any official documentation.

Kids’ Guesses:

3yo: This means LEGOs.
5yo: That picture means one black block, you need to find it.
7yo: There’s more than one block, but I don’t know where they are or how to find them.

Symbol 5 - Defined Piece and Axle Length

Finally, we’re into the meat and potatoes of building symbols. If you have a larger set with several axles or Technic bricks, it can be hard to make sure you’re picking the right one out of the pile. This symbol holds a few key pieces of information. First, the 1:1 indicates that the piece you need in that step is the same size as the picture in the actual instruction booklet, so you can place it on the picture and easily confirm if it’s the right piece.

Second, the smaller number in the circle or square lets you know the length of the piece you’re looking for in studs. So you could take an axle, place it next to a plate and measure its length. For example, the axle you need in the picture above is nine studs long. The younger members of our panel, who have less experience with sets containing multiple axles/Technic bricks, were stumped on this one.

Kids’ Guesses:

3yo: It means one and one and one. Three ones!
5yo: You need a piece with 11 dots on it.
7yo: This tells you how long the piece you need is to help you find it.

Symbol 6 - Rotate/Flip Your Build

This symbol tells you that you need to flip or rotate your build to add the next piece. It also belongs in the symbol hall of fame because our panel got a hat trick! Three out of three means this symbol is super clear and helpful.

Kids’ Guesses:

3yo: It means turn around, turn it around so you can play.
5yo: It says to turn it over!
7yo: Flip over your build or turn it to another side to keep going.

Symbol 7 - Sticker Application

Will our panel understand that this symbol is telling you two things? First, it’s time to apply a sticker, and then second, the number alerts you to know what numbered sticker you need. They might understand it better in context when you can see the sticker on the piece in the instruction booklet, but on its own was a challenge for some of the panel.

Kids’ Guesses:

3yo: This means one blanket!
5yo: It’s saying to turn the page.
7yo: That means use the sticker with the number one on it.

Symbol 8 - Projectile Warning

Stud shooters shoot studs, obviously, so this symbol hopes to help one avoid any eye injuries by cautioning you to be careful where you shoot studs. The red line through the middle was very helpful in the overall “don’t” message, but our panel struggled with what exactly the symbol was telling you not to do.

Kids’ Guesses:

3yo: This is a map, a red map, but don’t go on the map.
5yo: You can’t pick up a LEGO brick and throw it at yourself.
7yo: Don’t use the stud shooters to shoot at people’s heads.

Symbol 9 - Pieces Glow In The Dark

Some LEGO pieces glow in the dark, but since it’s difficult to build in the dark, this symbol lets you know that the piece you’re looking for glows in the dark. Regular white pieces and glow in the dark pieces can be almost indistinguishable in the light. As it’s a fairly busy for a symbol, with a sun and moon, as well as a two-tone shaded minifig head, it was by far the most difficult symbol for our panel.

Kids’ Guesses:

3yo: It says LEGO flashlight sun and moon. Sun and moon! It means sun and moon and yellow flashlight.
5yo: I don’t know, not even a little bit. Not one little bit do I know what that means.
7yo: There’s a shadow in the sun but no shadow in the moon.

Symbol 10 - Correct Orientation

If you’re at a building step where it’s easy to get the wrong orientation of a piece, LEGO will let you know with this quick symbol. The green check shows the correct orientation and the red X shows a potentially wrong way to build. This symbol is so easily understood that it gave us another perfect round from our panel!

Kids’ Guesses:

3yo: Check and X. One is good and one is bad.
5yo: The green one is right and the X is bad.
7yo: This shows you the right way to build. It should face like in the green check

Symbol 11 - Shiny/Metallic Piece

Often, a set will include elements, like this 1x2 modified tile with grille, in both a metallic color and flat or ‘regular’ silver. The tiny sparkle on the element in the instruction book lets you know to use the metallic grille in this step as opposed to a flat grille. The panel had mixed results with this one, but they all keyed into the sparkle, so LEGO is on to something.

Kids’ Guesses:

3yo: This is ‘nother LEGO flashlight, bright flashlight for LEGO.
5yo: This little sparkle says you have the right piece.
7yo: The piece you’re looking for is shiny.

Symbol 12 - Activate Light Brick

This symbol is a little bit more rare, as it only is seen when a set has a light brick. If you pull the tab, and then press the button on the back, light comes out. Again, this symbol provided some confusion for our panel.

Kids’ Guesses:

3yo: You have one LEGO, and one LEGO second. One and two! One and two!
5yo: I do not know. I do not know at all. Wait. I think I know. If you flip it over and pick that up, then flip it back over, then it’s ready.
7yo: If you pull the thing and push the button, the light comes out.

Overall, I’m pretty impressed with how many our panel got right. I can see how kids who don’t have a grownup to build with might be challenged by a few of them. The study of symbols is called semiotics and this little experiment made me realize just how difficult it can be to create them.

Imagine creating a picture indicating a direction without using words that works across all cultures and languages. I give LEGO pretty high marks for how far they’ve come, but our panel was less forgiving: “These pictures are hard. They need ones that work better for little kids.”

Best of BrickNerd - Article originally published October 11, 2023.

What symbol is your favorite? Did I miss any symbols you are aware of? Let us know in the comments!

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