Review: 21355 The Evolution of STEM from LEGO® Ideas

It's time to hit the books with LEGO® Ideas newest set, 21355 The Evolution of STEM, based on an Ideas submission from fan designer Daniel Bradley who kindly lent us some insight into the set.

 

The Evolution of STEM celebrates science, math and history with a collection of mini models bursting from the pages of a brick-built encyclopaedia. Without further ado let's book it to the new elements!

Products in this article were gifted by The LEGO Group; the author's opinions are their own.
This article contains affiliate links to LEGO.com; we may get a small commission if you purchase.

21355 The Evolution of STEM

• Release date: 1st March 2025
• Pieces: 879

• US$ 79.99 on LEGO.com US
• CA$ 99.99 on LEGO.com Canada
• GB£ 69.99 on LEGO.com UK
• AU$ 129.99 on LEGO.com Australia
• NZ$ 149.99 on LEGO.com New Zealand
• DE€ 79,99 on LEGO.com Deutschland
• NL€ 79,99 on LEGO.com Nederland
• FR€ 79,99 on LEGO.com France
• PLN 349.99 on LEGO.com Polska
• NOK 1099,90 on LEGO.com Norge
• DKK 699.95 on LEGO.com Danmark

Other countries click here

 

 

New moulds

Ideas sets don't typically contain new moulds so it's a nice surprise to see 4 brand new elements in 21355 The Evolution of Stem. I assume these elements weren't created specifically for the set (apart from the rigid hose, perhaps) so I'm sure we'll see these elements appear in more sets very soon.

• 4x Curve 1 x 6 in Tan (6544405)
• 1x Hose Rigid 3mm 25L in Black (6541885)
• 22x Beam 2L with Axle in Red (6531638)
• 6x Curve 2 x 6 Inverted in Tan (6544403)

Let's take a look at these elements in more detail:

Curve 1 x 6 in Tan (6544405)

A new slope with a unique arc. I couldn't find an exact match for the curve amongst existing curved slope but it lies somewhere between a 1x4 and 1x10 curved slope.

It was only last year that we saw a 1x6 slope added to the inventory; these two elements seem like they could be distantly related.

Further experimentation with the element found that the curve at the base of the 10x6 bubble canopy (50986 & 10312) was a pretty good match; still not perfect but a tad better than the slopes above.

22x Beam 2L with Axle in Red (6531638)

Remember the New Elementary Wishbrick Contest we held in 2022? I'm sure this was on somebody's list. This little element looks right at home among the other Technic liftarms with strange protrusions. It should be a powerful little element for creating a half-module offset in Technic builds.

Curve 2 x 6 Inverted in Tan (6544403)

We first spotted this piece in the upcoming F1 LEGO Speed Champions sets but now we have it in hand! 

The curve of this arch is an exact match for the existing 1x3 inverted arch (70681) however it is notably devoid of studs. The element's highest edge is a 2.5 plates tall (or 1 module). 

If it weren't so long I think I'd get a lot of use out of an element like this, but as is its size could make it difficult to incorporate in builds. Perhaps it might be used in a roof in conjunction with the pagoda plate.  

I'm keen to see where this element will appear next. Perhaps in a skateboarding sub-theme coming to LEGO City soon?

Recolours

• 12x Brick Curved 1 x 2 x 1 2/3 with 1 Cutout in Tan (6544404 | 5907) 

A curved slope that is a perfect quarter-circle. It's great to get this uniquely curved element in not only a new colour but also in such abundance. This is the fifth colour for the element; you can see it in pearl gold in our recent C-3PO fest.

• 4x Tile 1 x 2 with Stud Notch Left & Right in Pearl Gold (6508101 | 5091) & (6508086 | 5092)  
• 1x Tile 1 x 2 with Stud Notch Left in Sand Blue (6532266 | 5091) 

While the set contains equal numbers of right and left version of the element in pearl gold, we only receive a single left-handed sand blue tile. For a completionist like myself this is quite frustrating. I hope we don't have to wait too long before we can make a matching pair.

• 5x Technic Axle Connector Smooth [with x Hole + Orientation] in Coral (6544409 | 59443) 
• 5x Technic Axle Connector Smooth [with x Hole + Orientation] in Dark Turquoise (6548959 | 59443) 

Seeing these 2 colours together makes me want to explore this colour combo further. It's nice to see a new Technic element in coral as there are so few in the LEGO inventory.

• 6x Plate Round 1 x 1 with Hollow Stud and Underside Clip in Blue (6537695 | 5264) 
• 3x Bar 2L with Towball in Dark Azure (6544408 | 22484) 

The towball element is useful both functionally and decoratively so a new colour is most welcome. I'm glad to be adding more of that game-changing new clip to my collection too!

• 2x Plant, Leaf 2 x 6 x 1 with 2 Studs in Trans-Clear (6548957 | 3565) 
• 1x Brick Curved 1 x 2 x 1 with Curved Top in Trans-Light Blue (6526019 | 5841) 

The perfect elements to represent insect wings and flowing water, as we'll see later when we build the model. These will surely be popular among MOC builders.

New prints

Decorations for The Evolution of STEM come courtesy of both printed elements and stickers:

• 1x Tile 1 x 1 with Groove with print in Bright Green (6468472 | 3070bpr) + 1 spare
• 2x Tile 1 x 2 with Groove with print in Light Aqua (6527761 | 3069bpr) 
• 1x Tile Round 1 x 1 with print in Trans-Clear (6527760 | 98138pr) + 1 spare
• 1x Tile 1 x 1 with Groove with print in Glow in Dark White (6527759 | 3070bpr) +1 spare

Quite an eclectic selection of prints! Surprisingly, the 'meow bits' print was designed for this set, as a reference to fan designer Daniel Bradley's cat, but I wonder if we will see it get wider use in future sets.

There is a printed element of my cat Zeus, he was probably the most important one for me to include (no offence to my partner and brother) and I am so happy with the design that Nathan (LEGO Graphics) was able to draw up for him.

In this set it's used as a billboard in a micro city, as is the green 1x1 tile. I'm not sure what original purpose the green element serves but I get a Minecraft vibe form that pixelated design. A new peanut print provides a healthy snacking option for our minifigures. But the Radium printed tile is my favourite: Glow in the Dark White is the perfect choice for that radioactive element!

Sticker sheet

A mercifully small sticker sheet accompanies The Evolution of STEM. Though it contains just a few decorations, they'll be applied to the desk mini model that sits front and centre of the model so they contribute a lot to the finished piece. Despite the size of the sheet, the graphic design team have included an impressive number of scientific and mathematical references like the advent of the internet on the computer display (1), Pythogoras' theorem, golden ratio, and Mendel's pea plant on the chalkboard (2), and the Golden Record that was sent into space with The Voyager 1 spacecraft (3).

Daniel Bradley helped us decipher a few more of the easter eggs:

29.2 is my anniversary with my partner, it being on a leap year saves us money celebrating once every four years! The T G on the books is a nod to my brother, we are very close and I wanted to be able to include him.

Minifigures

The Evolution of STEM includes 3 minifigures all of which include new decorations and rare elements in some capacity. From left to right:

English Physicist and Mathematician Isaac Newton:

• 1x Torso with print in Sand Green (6546844 | 973pr) 
• 1x Hair Long Wavy/Curly in Medium Stone Grey/ Light Bluish Gray (6473817 | 2632)
• 1x  Hips with White Legs and Black Boots Pattern in White (6122685 | 21019) (970c27pat03)

Polish physicist and chemist, Marie Skłodowska-Curie:

• 1x Torso with print in Black (6546834 | 973pr) 
• 1x Hair Top Knot Bun [Plain] in Sand Yellow/ Dark Tan  (6547112 | 93217, 5958, 86400) 

and American agricultural scientist and inventor. George Washington Carver:

• 1x Torso with print in Reddish Brown (6546832 | 973pr) 
• 1x Head with New face print in Umber Brown 6527753 
• 1x Hat / Flat Cap, Old Style in Dark Brown (6501311 | 2514) 

I always find it interesting to see famous historical figures represented in LEGO form. The decorations are generic enough to be easily recycled into your own characters. I particularly like the printing on George Washington Carver's torso featuring a flower design that has its roots firmly in the LEGO universe.

While the figures are nice, I can't help but think that this is was a missed opportunity to include some universally recognised scientific personalities like Albert Einstein or Charles Darwin.

Rare elements

The following elements appear in three sets or fewer:

• 1 x Bar 3L in Earth Green/ Dark Green (6525789 | 87994) in 1 other set
• 2 x Plate 1 x 3 in Dark Brown (6013832 | 3623) in 2 other sets
• 1 x Bracket 1 x 2 with 1 x 2 Vertical Studs in Black (6530055 | 4585) in 2 other sets
• 1 x Window 4 x 3 Lattice with Rounded Top in Dark Orange (6468833 | 5260) in 2 other sets
• 2 x Plate Special 1 x 1 with Vertical Tooth in Bright Green (6446106 | 15070) in 2 other sets
• 3 x Plant, Flower, Peony Rose with 2 Layers in White (6551129 | 5904) in 1 other set
• 1 x  Tile Round 2 x 2 with Bottom Stud Holder with 'C' on Black Background Print in Medium Stone Grey/ Light Bluish Gray (6352997 | 79403) (14769pr1211) in 2 other sets
• 9 x Plate Round 1 x 1 with Hollow Stud and Underside Clip in Black (6534180 | 5264) in 1 other set
• 1 x Plate Special 1 x 1 with Hole Through Stud, 3 Bars and 3 Bar Holes in Reddish Brown (6492629 | 1941) in 2 other sets
• 1 x Slope 33° 2 x 2 Double / Inverted in White  (6507816 | 1762) in 2 other sets
• 1 x Technic Axle Connector Smooth [with x Hole + Orientation] in Reddish Orange (6483787 | 59443) in 1 other set
• 1 x Tile 4 x 4 in Reddish Brown (6488484 | 1751) in 1 other set

The build

The build begins by constructing a base upon which all the subsequent mini models will be displayed. In this case, it’s an open book using the new curved slopes to create the pages. There are some nice design touches like the use of 1x2 wedges to create creases in the book cover around the spine. The spine itself hides a simple mechanism to provide some movement to the model: the central Technic connector moves vertically thanks to a cam underneath and this will bounce the Carbon atom up and down and the trans clear 2x2 brick rotates, providing movement to the DNA strand.

A couple of little easter eggs hide within this tome: hidden on one side of the book under our new inverted arches is a collection of 1x1 tiles representing the electromagnetic spectrum and on the other, STEM written out in morse code. A fun touch but I wish the designers used just a little bit of space to include that missing right handed sand blue notched tile. Perhaps the designer should have taken a leaf out of LEGO Speed Champions, who managed to fit all the complementary tiles and wedges into their BMW race cars.

The focal point of the model is a colourful DNA spiral. The structure is well realised with the new red Technic liftarms providing the sugar phosphate backbone and 4 colours of Technic connector to represent the 4 nucleotides. The DNA is built by stacking sub units atop each other at an offset to create a spiral. It’s a cool effect so we’ll overlook the fact that DNA is almost always a right-handed helix, rather than the left-handed spiral built in the set. Oops!

The pages of the book are slowly filled in with a number of clever mini builds. The first is a micro city. The ground of the city is attached to the book simply by a couple of hinge bricks but the designers have cleverly matched the angle at which it sits to a 1x6 slope for a nice clean finish. The new printed tiles make nice billboards but the best NPU is the tiny plane with a propeller represented by a trans-clear saucer (38799).

 

On the opposite page sits an apple tree. This is not the first time we've seen Dragon Horn/ Tail (2142) used to build a tree trunk, but it's the perfect part for such an application. The special plate with bars and holes (1941) works well to provide connection points for the branches.

A few more mini models populate the base which range in complexity from the simple garden and robotic arm to the more involved old-fashioned automobile. The laboratory requires three stickers and looks quite unfinished without them applied.

The Carbon atom takes advantage of the special plate with bars and holes (1941) to position the protons and neutrons (represented by Bionicle spheres and towballs) in the atom's nucleus. A peak at the back shows off some of the structure of this build as well and we can see that the designers have secured the model with a third blue towball to make sure all sub atomic particles are present and correct in this Carbon-12 atom.

Three more mini models finish off the build: a Voyager 1 satellite, a space shuttle, and a honeybee. The special plate with bars and holes is used once again to provide the central connection point for the spacecraft's various armatures and equipment. The shuttle is another simple build; mostly studs up but with a neat use of D-SNOTS at the tail end to provide a subtle angle for the thrusters. The honeybee is the most complex and parts intensive. The segments of the body are connected to one another via the new inverted clip. The stand out parts usage here are those new trans clear petals - don't they look great as wings?

Finished Build

With all the components in place, the finished model is a bright and busy celebration of humanity's scientific achievements. The 879 pieces of the model go a long way, with the DNA strand and connected mini builds erupting from the set providing some height and volume.

I like the composition of the model: the builds on the two pages are nicely balanced, and the subtle angles of the tree on one side and city on the other gives the effect of the model springing from the page. 

The model is dense with detail but still provides a little space to place the three minifigures.

With the figures in place, the model comes to life with that classic LEGO humour.

Insight from fan designer Daniel Bradley

We reached out to Daniel Bradley, who submitted the original design to LEGO Ideas to ask a few questions about the set.

New E.: What inspired your original Ideas submission and how did you decide what to include in your submission?

Daniel: Looking back on my approach to the challenge on LEGO Ideas, I find it interesting that it has come full circle. Initially I designed a series of dioramas featuring various historic icons in STEM but later realised that I couldn’t reference any potential intellectual property. That led me to a new idea, inspired by a childhood memory of a big encyclopaedia for kids that I had—to create a book bursting with knowledge. Naturally I kept the minifigures generic while still representing different areas within STEM. And now with the final product I’m back to celebrating the historic icons I originally wanted to highlight!

New E.: Can you walk us through the changes made by the LEGO design team?

Daniel: Working with the Ideas team was great fun and I really appreciated the opportunity to be as involved as I was. Overall I think the core of my original design has stayed true to the model, with the open book, rocket, bee and various other elements. What the LEGO designer (Ollie) has done so well is not only improving the building technique but also expanding on my model without making it feel too cluttered. I really admire the talent of the LEGO team—I still have a long way to go in my design skills, haha!

The biggest addition to the set is obviously the DNA helix and its ability to spin. This really impressed me as I mostly build digitally and don’t often get to experiment with cogs and gears!

New E.: What’s your favourite aspect of the final set?

Daniel: My favourite piece is definitely the tile with Zeus! I love him so much so being able to include him was really nice of the team, especially for it to be a drawn graphic of him! I haven’t built the set yet but i am fairly certain my favourite mini build will be the bee that comes off the DNA helix.

Closing thoughts

As someone who has always had an interest in science, I had a lot of fun with this set. The set does a great job at showcasing and celebrating some of the most important advancements in the various fields of STEM with a diverse selection of fun and interesting small builds. The variety of techniques and elements on offer provided a great experience; each bag of parts has you building something different every time which keeps things fresh and exciting. 

The medium of LEGO is a wonderful way to introduce these ideas to younger builders with each mini-build providing a new learning point. The model crams a lot in to a relatively small space so there's a wealth of knowledge to discover. This would be a great set to build with a child or to give to one for STEM aspirations.

As for parts, 876 elements at this price point seems like a pretty average deal. The piece count includes 3 exclusive figures, some novel new prints and a decent quantity of new moulds and recolours which goes some way to justify the price, if the building experience and educational value wasn't enough.

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