BlockTalk Find Your Set

Free tool

LEGO Missing Piece Checker

Rule out the usual hiding places first. If the piece really is gone, check the set piece by piece and leave with the element ID LEGO asks for, or a link to buy the part.

Science Kit Year 4-6

Checking

45621 Science Kit Year 4-6

318 pieces in 87 part and color combinations, plus 6 minifigures.

The official piece count includes the 18 parts inside the set's minifigures, which this inventory lists separately. Spare parts are counted in neither figure.

Before you call it missing

Builders who report a missing piece often find it in one of these places. Tick each one off as you look.

Show

Piece checklist

Bricks 82 pieces

  • Brick 1 x 6 Bright Light Orange Part 3009 Element 6186542 ×4
  • Brick 2 x 4 Bright Light Orange Part 3001 Element 6100027 or 4645053 ×4
  • Brick 1 x 4 Coral Part 3010 Element 6422918 ×4
  • Brick 2 x 2 Coral Part 3003 Element 6422920 ×4
  • Brick 1 x 2 Dark Blue Part 3004 Element 4249891 ×8
  • Brick 2 x 4 Dark Blue Part 3001 Element 6275133 or 4530029 ×4
  • Brick 2 x 8 Dark Blue Part 3007 Element 6482811 or 4649966 ×4
  • Brick 1 x 1 with Simple Black Eye with White Pupil Print Dark Turquoise Part 3005pr0003 Element 6565255 ×4
  • Brick 1 x 2 x 2 with Inside Stud Holder Dark Turquoise Part 3245c Element 6428472 ×4
  • Brick 1 x 8 Dark Turquoise Part 3008 Element 6289133 ×4
  • Brick 2 x 2 Dark Turquoise Part 3003 Element 6314091 or 4120399 ×4
  • Brick 2 x 2 Medium Nougat Part 3003 Element 6058085 or 4645062 ×4
  • Brick 2 x 2 x 3 Medium Nougat Part 30145 Element 6482742 ×4
  • Brick 2 x 6 Tan Part 2456 Element 4181134 or 4143256 ×4
  • Brick 1 x 2 without Bottom Tube Trans-Light Blue Part 3065 Element 6514268 or 6244910 ×2
  • Brick 1 x 2 without Bottom Tube Trans-Yellow Part 3065 Element 6514265 or 6244907 ×2
  • Brick 1 x 1 with Simple Black Eye with White Pupil Print White Part 3005pr0003 Element 4569080 ×10
  • Brick 2 x 2 White Part 3003 Element 6552095 or 6548256 ×4
  • Brick 2 x 4 White Part 3001 Element 6552094 or 300101 ×4

Bricks Round and Cones 44 pieces

  • Cone 1 x 1 [Top Groove] Dark Turquoise Part 59900 Element 6482735 ×6
  • Brick Round 2 x 2 with Axle Hole Reddish Brown Part 3941 Element 4211166 ×2
  • Brick Round, Half 1 x 2 Tan Part 68013 Element 6351413 ×4
  • Cone 1 x 1 Inverted with Bar at Bottom (Ice Cream Cone) Tan Part 11610 Element 6538442 or 6017003 ×6
  • Brick Round 2 x 2 with Axle Hole Trans-Light Blue Part 3941 Element 6514282 or 6273153 ×2
  • Cone 1 x 1 [Top Groove] Trans-Yellow Part 59900 Element 6514022 or 6337597 ×10
  • Brick Round Corner 2 x 2 Macaroni with Stud Notch and Reinforced Underside [New Style] White Part 85080 Element 6619303 or 6078115 ×8
  • Cone 1 x 1 [Top Groove] White Part 59900 Element 6601844 or 4518400 ×6

Bricks Curved 32 pieces

  • Brick Curved 1 x 3 x 2 Inverted [Inside Bow] Bright Light Orange Part 18653 Element 6172370 ×4
  • Brick Curved 2 x 3 Bright Light Orange Part 6215 Element 6334834 ×4
  • Brick Curved Inverted 2 x 4 Double Bright Light Orange Part 5174 Element 6468850 ×2
  • Brick Curved 1 x 2 x 1 No Studs Coral Part 37352 Element 6261293 ×4
  • Brick Curved 1 x 3 x 2 Coral Part 33243 Element 6482750 ×4
  • Brick Curved 4 x 1 Double, No Studs Dark Turquoise Part 93273 Element 6249299 ×4
  • Brick Curved 6 x 1 Dark Turquoise Part 42022 Element 6465246 ×4
  • Brick Curved 1 x 2 x 1 No Studs White Part 37352 Element 6552172 or 6248827 ×4
  • Brick Curved Inverted 2 x 4 Double White Part 5174 Element 6461062 ×2

Plants & Trees 24 pieces

  • Plant, Grass Stem with Bar Hole [3.2mm] Bright Green Part 15279 Element 6566117 or 6413056 ×4
  • Plant, Leaf 2 x 6 x 1 with 2 Studs Bright Green Part 3565 Element 6510105 or 6433394 ×4
  • Plant, Plate 1 x 1 Round with 3 Leaves Bright Green Part 32607 Element 6182261 ×4
  • Plant, Flower, Plate Round 1 x 1 with 5 Petals Coral Part 24866 Element 6295242 ×6
  • Plant, Flower, Plate Round 1 x 1 with 5 Petals White Part 24866 Element 6206149 ×6

Plates Special 22 pieces

  • Plate Special 2 x 2 with Rubber Foot Black Part 109373 Element 6492701 ×4
  • Plate Special Round 2 x 2 with Center Stud (Jumper Plate) Dark Blue Part 18674 Element 6253885 ×4
  • Bracket 1 x 2 - 2 x 2 Light Bluish Gray Part 44728 Element 6117967 or 6009014 ×4
  • Plate Special 2 x 2 x 2/3 with Axle Hole and Grill on Sides (Haybale) Tan Part 71752 Element 6330903 ×4
  • Plate Special 1 x 1 with Vertical Tooth White Part 15070 Element 6615559 or 6046905 ×6

Bricks Special 20 pieces

  • Brick Special 1 x 2 with 1 Center Stud on 1 Side, Bottom Stud Holder Bright Light Orange Part 86876 Element 6455791 ×4
  • Brick Special 2 x 2 with Photo Clip Bright Light Orange Part 5252 Element 6482579 ×2
  • Brick Special 2 x 4 with 3 Axle Holes Dark Turquoise Part 39789 Element 6482741 ×4
  • Brick Special 1 x 2 with Pin - Bottom Stud Holder Light Bluish Gray Part 44865 Element 6321770 ×4
  • Brick Special 2 x 4, with 2 x 2 Brick with Top Pin and 1 x 2 Side Plates Light Bluish Gray Part 30592 Element 6301425 or 6278504 ×2
  • Brick Special 1 x 2 with 2 Studs on 1 Side Medium Nougat Part 11211 Element 6411587 ×4

Plates Round Curved and Dishes 17 pieces

  • Plate Round Corners 4 x 4 x 2/3 Circle with Reduced Knobs Bright Light Orange Part 66792 Element 6308882 ×4
  • Plate Round Corners 8 x 16 x 2/3 Circle with Reduced Knobs Dark Blue Part 5251 Element 6531173 ×1
  • Plate Round Corners 8 x 16 x 2/3 Circle with Reduced Knobs Dark Turquoise Part 5251 Element 6482578 ×2
  • Plate Round Corners 8 x 8 x 2/3 Circle with Reduced Knobs Medium Nougat Part 66790 Element 6509766 or 6301649 ×2
  • Plate Round 1 x 1 Swirled Top / Poo Reddish Brown Part 53119 Element 6438899 or 6275030 ×6
  • Dish 3 x 3 Inverted [Radar] White Part 43898 Element 4179580 ×2

Tiles 14 pieces

  • Tile 1 x 2 with Groove Bright Light Orange Part 3069b Element 4622062 ×5
  • Tile 1 x 6 with Groove Bright Light Orange Part 6636 Element 6365966 or 4654129 ×4
  • Tile 1 x 2 with Groove Dark Blue Part 3069b Element 6554190 or 4528488 ×5

Plates 12 pieces

  • Plate 2 x 6 Bright Light Orange Part 3795 Element 6097509 ×4
  • Plate 2 x 12 Dark Turquoise Part 2445 Element 6453950 ×2
  • Plate 2 x 8 Dark Turquoise Part 3034 Element 6257063 ×2
  • Plate 2 x 12 White Part 2445 Element 6552091 or 244501 ×2
  • Plate 2 x 8 White Part 3034 Element 6552101 or 303401 ×2

Technic Bricks 10 pieces

  • Technic Brick 1 x 2 with Axle Hole Type 1 [+ Opening] and Bottom Pin Coral Part 32064a Element 6439447 ×4
  • Technic Brick 1 x 2 [1 Pin Hole] White Part 3700 Element 6619284 or 370001 ×6

Technic Axles 6 pieces

  • Technic Axle 4 Black Part 3705 Element 370526 ×2
  • Technic Axle 3 Yellow Part 4519 Element 6130007 ×2
  • Technic Axle 7 Yellow Part 44294 Element 6130009 ×2

Tubes and Hoses 6 pieces

  • Flexible Ribbed Hose 8mm Ends 10L Black Part 27328 Element 6454757 or 6253307 ×2
  • Flexible Ribbed Hose 8mm Ends 19L Flat Silver Part 57539 Element 6044636 or 4615232 ×4

Wheels and Tyres 6 pieces

  • Wheel Smooth 24 x 14mm with Pin Hole Black Part 5253 Element 6482581 ×4
  • Wheel 43 x 14 with 4 Spokes, Axle Hole, and Black Integral Tire Coral Part 65834pat0001 Element 6482584 ×2

Energy Effects 4 pieces

  • Wave / Flame Rounded with Base Rim Trans-Orange Part 6126b Element 6167741 or 4261397 ×4

Panels 4 pieces

  • Panel 1 x 2 x 2 [Side Supports / Hollow Studs] Trans-Light Blue Part 87552 Element 6581813 or 6253230 ×4

Tiles Round and Curved 4 pieces

  • Tile Round 2 x 4 White Part 66857 Element 6329902 ×4

Electronics 3 pieces

  • Control Unit / Remote Control, Science White Part 115901 Element 6666324 or 6586717 ×1
  • Motor 10 x 6 x 3, Science White Part 118091 Element 6669513 or 6610998 ×1
  • USB Cable White Part 114253 Element 6554054 ×1

Animal / Creature Body Parts 2 pieces

  • Animal Body Part, Clam / Scallop Half Shell with 4 Studs White Part 18970 Element 6550156 or 6097097 ×2

Non-System Parts 2 pieces

  • Activity Card 11 for Science Kits [No Color/Any Color] Part 114342 Element 6559822 ×1
  • Activity Card 16 for Science Kits [No Color/Any Color] Part 114349 Element 6559904 ×1

String, Bands and Reels 2 pieces

  • Technic Rubber Belt Large [33mm ID] [Round Cross Section] Yellow Part 85546 Element 4544151 or 70905 ×2

Minifig Headwear 1 piece

  • Helmet, Sports, with Vent Holes [Plain] Coral Part 46303 Element 6397831 ×1

Tools 1 piece

  • Brick and Axle Separator v2.0 Dark Turquoise Part 96874 Element 6254100 ×1

Minifigures 6 figures

  • Monochrome Bright Green Minifigure, checked as a whole figure ×1
  • Monochrome Red, 28621 Head Minifigure, checked as a whole figure ×1
  • Monochrome Blue Minifigure, checked as a whole figure ×1
  • Monochrome Bright Light Orange, 28621 Head Minifigure, checked as a whole figure ×1
  • White Torso, Dark Blue Legs, Neutral Face Minifigure, checked as a whole figure ×2

Tick each piece as you find it, or mark it missing.

When a piece really is missing

Ask LEGO

LEGO takes requests for pieces missing from a new set through its customer service site. The form asks for the set number and each piece's element ID, the number printed beside the piece in the parts list at the back of the instructions. This checker lists both.

Request a replacement from LEGO

Buy the piece

Mark a piece missing and your list links it to an eBay search for that part, which also covers pieces from older or second-hand sets.

Keep a record

Copy or download your missing list (the CSV opens in any spreadsheet), or print the whole checklist and tick pieces off on paper. Your marks stay in this browser, so you can check a big set over several sittings.

We value your privacy

We use cookies 🍪 for analytics and to improve your experience. Read our privacy policy