10 functional 3D printing projects for high school students (with dimensions)
Ten projects that fit something real, from a desk clip to an Arduino case: the dimensions to measure, the prompt, and the design idea each one teaches.A good school project has three things: a real object it must fit, a measurement that decides whether it works, and a print short enough for a shared printer. These ten are ordered from a first lesson to an end-of-term project. Each lists the numbers to measure, what it teaches, and a rough print time at 0.2 mm layers.
The ten projects at a glance
| # | Project | Measure | What it teaches | Rough print |
|---|---|---|---|---|
| 1 | Desk cable clip | Desk edge thickness, cable diameter | Clearance, a snap opening | 20 min |
| 2 | Name tag with a hole | Nothing: 60 × 20 × 3 mm | Text, holes from an edge | 15 min |
| 3 | AA battery tray | AA: 14.5 × 50.5 mm | Patterns, drop-in fit | 45 min |
| 4 | Knob for a 6 mm D-shaft | Shaft diameter and flat | Press fit, a keyed hole | 30 min |
| 5 | Headphone hook under a desk | Desk thickness, headband width | Load, screw holes | 1 h |
| 6 | Pegboard tool holder | Hole pitch and size of your board | Locating pegs, the tool's outline | 45 min |
| 7 | Phone stand | Phone thickness with case | Angles, centre of gravity | 2 h |
| 8 | Gridfinity bin | 42 mm grid, 7 mm height units | Standards, dividers | 1 h |
| 9 | Robot sensor bracket | Sensor board, chassis holes | Hole patterns, stiffness | 40 min |
| 10 | Arduino Uno enclosure | Board 68.6 × 53.4 mm, ports | Ports, standoffs, a lid | 2.5 h |
Print times are estimates for a typical bed slinger; a fast CoreXY printer often halves them. The online slicer gives the real time and grams for your printer before anything is queued.
The projects
1. Desk cable clip. The best first lesson because every student has a desk edge. The opening is the desk thickness plus about 0.3 mm per side, and the cable snaps in through a gap a little narrower than the cable. Students learn that one number decides the fit. The one-period lesson plan is built on it.
2. Name tag. Not a functional part, but it teaches placing features by distance: a 5 mm hole 5 mm from the end, letters engraved 0.6 mm deep. Good on a day when calipers are short.
3. AA battery tray. An AA cell is about 14.5 mm across and 50.5 mm long. Students size one pocket (15.5 mm with 0.5 mm clearance), then repeat it in a row or a grid. Duplicate does that by hand, so the pocket spacing is a number they choose, not a guess.
4. Knob for a D-shaft. Pots and small motors use 6 mm D-shafts. The hole must grip the shaft and the flat must stop it spinning: a press fit with almost no clearance. Expect a reprint, and make the reprint part of the grade.
5. Headphone hook. Screws under a desk or clamps on its edge. It teaches load: a thin arm bends, a rib does not. Have students hang a bag on it and explain where it failed.
6. Pegboard tool holder. Measure your own board: many have 1/4 inch (6.35 mm) holes on 1 inch (25.4 mm) centres, others differ, and IKEA's Skådis uses slots. The pegs must locate in the holes; the holder must fit the tool's outline. Two fits in one part.
7. Phone stand. The phone's thickness with its case, an angle between 60° and 70°, and a slot for the charging cable. Students discover that a tall stand tips over and fix it with a longer base.
8. Gridfinity bin. A real open standard: 42 mm grid, 7 mm height units. Students design a bin for the things in their own drawer and learn why standards exist. The Gridfinity guide has the numbers.
9. Robot sensor bracket. For the robotics club: a mount that holds a distance sensor at a set height and screws to the chassis. Measure the board and the hole spacing (edge to same edge), then check the hole pattern with Measure before printing.
10. Arduino Uno enclosure. The end-of-term project: the board is 68.6 × 53.4 mm with four mounting holes, a USB port and a power jack on one side. Standoffs, port cutouts and a lid that stays on. The Arduino Uno enclosure guide has the hole positions.
How students make them
Every project can be described to the AI as a sentence with its numbers, or shaped by hand from a box, a plate or a cylinder with the hole, cut, add, extrude, text, round, fillet, shell and measure tools. Most students mix the two: they describe the part, then move a hole or round a corner by hand. Before any project, how to measure an object for a 3D printed part is worth ten minutes of class time, and how much clearance to leave is the handout for every fit in this list.
Projects 3, 6 and 8 can be started from a photo of the drawer or the board too: photo to part reads a picture taken next to a ruler.
Credits for a term of projects
The hand tools (hole, cut, add, extrude, text, round, fillet, shell and measure) are free on any account, and so is downloading what you shape with them. With the AI, a new part spends 4 credits on a plan with its first 3 small changes free, a design change 3, a small change 2, a quick edit 1, so a seat's 25 credits cover 5 or 6 new AI parts a month with their small changes. A term with these ten projects, where students build some by hand and describe the harder ones, fits in a seat's monthly credits for most students. Hand-shaped work never spends any.
An Education seat is $3 a month, or $30 a year (2 months free), taxes included. Each seat puts 25 credits a month on the student's own account, with every STL, 3MF and sliced G-code download included and the online slicer up to 60 files a day. The high school page explains how a department sets it up.
Prompts to start from
Open one in the builder, change the numbers to yours, and the model renders in your browser, usually within a minute or two. Keep adjusting in the chat before you print.A tray for eight AA batteries standing up in two rows of four, 15.5 mm round pockets 30 mm deep, 2 mm walls, a finger notch on each long side
A knob 30 mm across and 18 mm tall for a 6 mm D-shaft with a 4.5 mm flat, press fit, knurled grip, a pointer line on top
A phone stand for a phone 9 mm thick in its case, 65 degree angle, 80 mm wide, a 12 mm slot at the bottom for the charging cable
An enclosure for an Arduino Uno 68.6 x 53.4 mm with 6 mm standoffs on its four mounting holes, cutouts for the USB-B port and the barrel jack, 2 mm walls and a lid that stays on but lifts off by hand
Questions
Parts that fit something real: a desk cable clip, a battery tray, a knob for a D-shaft, a pegboard holder, a phone stand, a Gridfinity bin, a robot sensor bracket and an Arduino enclosure. Each has a measurement that decides whether it works, which is what makes it a design lesson.
Small parts like clips and tags print in 15 to 30 minutes, brackets and trays in under an hour, stands and enclosures in two to three hours on a typical printer. Slice first to get the real time for your printer.