Academics
PopForge
Pop-up engineering. Pick a card, or set the distances and panel lengths yourself, and guess: will it fold flat, poke out of the closed card, or not fold properly? Then open and close it in 3-D and see the rule in numbers: a pop-up works when it's a parallelogram. Print the template, cut, fold and glue.
▶ Play it nowBuilt for sittings of about 20 minutes on the screen. That is our design budget, not a measurement.
Meet your mentor
Every Spark & Anvil app has a friendly mentor character that demonstrates, asks, and patiently scaffolds learning.
Mentored by Hingely
#8a3b12 Characters who teach
Meet the cast
PopForge's paper engineers each know one rule of pop-ups. Hingely watches the spine, Flatsy checks that a design folds flat, Pokey spots the ones that poke out of a closed card, and Gluey knows where the tabs go.
Hingely
everything turns about the spine, the fold in the middle of the card
Flatsy
A flat-folding lizard - a pop-up folds flat when it is a parallelogram: opposite sides equal
Pokey
A curious heron - closed, the fold sits depth plus height from the spine, so too big pokes out
Gluey
A beaver with glue - the panels must add up to the distance they lie along, or the paper tears or bows
What's inside
Learning goal
Pop-up engineering. Pick a card, or set the distances and panel lengths yourself, and guess: will it fold flat, poke out of the closed card, or not fold properly? Then open and close it in 3-D and see the rule in numbers: a pop-up works when it's a parallelogram. Print the template, cut, fold and glue.
Mentored by Hingely — no data leaves the device.
How PopForge handles your kid's data
- ✅ All progress, settings, and AI-generated content stays on the device
- ✅ No analytics, no tracking, no third-party SDKs
- ✅ Free — no ads, no in-app purchases
- ✅ No personal information collected from children — in line with COPPA (updated by the 2026 FTC amendments)
- ✅ No chat with strangers — play-together rooms use a short code and preset emotes, never typed messages