Rotor-drop comparison
Observe passive rotation under a controlled release instead of throwing a model.
Adult planning suggestion: about6–9 · Observation & recall
- Players
- 3 per group
- Time
- 20–25 minutes
- Materials
- Two 180×60mm paper rotor templates, adult-assisted scissors, ruler and optional timer.
Prepare
An adult cuts each 180×60mm rectangle: split the top 90mm along the centre into two 30mm-wide blades. At the 90mm line, cut inward 20mm from each side, leaving a 20mm central body connection. Fold the lower side panels inward to narrow the body; fold the two upper blades in opposite directions.
Play
Hold the model by the body and release, without throwing, from the same measured height about 1m above a clear floor. No standing on chairs is needed. One learner releases, one watches rotation and one records. Retrieve only after it lands; use paper only, with no batteries, lights or added hard weights.
Worked example
Make three releases of model A. For model B change only the two blade fold angles, keeping paper, cut shape and release height fixed, then repeat three times. Record rotation seen yes/no and, if timing, each raw time. The sheet contains blank observations because no flight result is guaranteed.
Finish and check
Compare repeat patterns, not a single fastest drop. A hand stopwatch on a short fall has large reaction-time uncertainty; small differences are not reliable evidence of better design. A non-rotating drop is still a valid observation. End after six recorded releases and a sentence about the variable changed.
Adaptation and limits
A class of thirty can use ten trios at clear stations or take turns at fewer supervised spaces. Adults may pre-cut and learners may direct rather than release. Science Buddies discusses paper-helicopter engineering; our dimensions and paper-only comparison are separate and were not physically flight-tested for this page.
Purpose, observation and provenance
Within this activity: Observe passive rotation under a controlled release instead of throwing a model.
Ask what changed, what stayed fixed and whether a small timed difference exceeds measurement uncertainty.
Our rules, examples and printable diagrams are separately prepared. The earliest inventor of the broader mechanism is not established here.
Science Buddies — Engineer Helicopters for Mars — Paper-rotor design background; our original template and no-electronics trial are separate.
Age bands are planning suggestions. Goals describe observable actions, not measured long-term gains or institutional endorsement.
Free alternative: Copy the supplied grids, labels and cards onto reused paper. No specialist product is needed. Adults may prepare pieces or act as a scribe.
Printable materials
Preview at 100% scale, with browser headers and footers off. Cut with suitable help. Keep host keys separate. This is a manual tabletop kit, not an online opponent, automatic judge or solver.
Player materials · Rotor-drop comparison
180×60mm template; blade split 0–90mm; side cuts 20mm at 90mm.
Model / trial 1,2,3 / same height? / rotation? / optional raw time.
Adult cuts solid lines; folds dotted lines. Original paper-only template,60×180mm.
Additional pieces / private cards
Second identical rotor template: label this completed model B.
Adult cuts solid lines; folds dotted lines. Original paper-only template,60×180mm.
Player record · keep host key separate
| Model/trial | Height | Rotation | Time(optional) |
|---|---|---|---|
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
| ________ | ________ | ________ | ________ |
Host key · separate from players
No fixed flight time or winner. Keep paper/cut/release height fixed; change only blade angles.
Run the round
An adult cuts each 180×60mm rectangle: split the top 90mm along the centre into two 30mm-wide blades. At the 90mm line, cut inward 20mm from each side, leaving a 20mm central body connection. Fold the lower side panels inward to narrow the body; fold the two upper blades in opposite directions.
Hold the model by the body and release, without throwing, from the same measured height about 1m above a clear floor. No standing on chairs is needed. One learner releases, one watches rotation and one records. Retrieve only after it lands; use paper only, with no batteries, lights or added hard weights.
Make three releases of model A. For model B change only the two blade fold angles, keeping paper, cut shape and release height fixed, then repeat three times. Record rotation seen yes/no and, if timing, each raw time. The sheet contains blank observations because no flight result is guaranteed.
Compare repeat patterns, not a single fastest drop. A hand stopwatch on a short fall has large reaction-time uncertainty; small differences are not reliable evidence of better design. A non-rotating drop is still a valid observation. End after six recorded releases and a sentence about the variable changed.
A class of thirty can use ten trios at clear stations or take turns at fewer supervised spaces. Adults may pre-cut and learners may direct rather than release. Science Buddies discusses paper-helicopter engineering; our dimensions and paper-only comparison are separate and were not physically flight-tested for this page.