AP Physics C / Honors Physics
Trebuchet Project
The third nine weeks project is optional. Since
everyone must have an equal number of
summative grades, if you choose not to participate,
you will be taking a standard test on a designated
day to earn your grade. The test will have twenty
multiple-choice and three free-response questions
and will be taken outside of class in zero block or
after school. There will be no test corrections for
this test.
materials and the last picture should be of the
completed product. You will also be required to
complete a calculations page that determines the
efficiency of your machine. Since you will need
some of the numbers from your practice launches,
the calculations page needs to be turned in before
the end of school on February 16th.
There is no size requirement but traditionally they
end up being around 4-6 feet tall. You will be
graded according to the attached rubric. Part of the
rubric is based on a peer review that you will
confidentially complete for each of your group
members. Additionally, the rubric will assess the
durability and performance of your trebuchet. There
are two five-point bonuses that you win: farthest
launch and best presentation
Some ways to win this vote are to have the most
entertaining presentation, best performance, or
best-themed group. It’s completely up to the
individual student how they vote.
For this project, you and 0-3 friends will be building
a trebuchet and will be presenting it during the
Medieval Festival on February 9th. Trebuchets are
a type of catapult that uses the mechanical
advantage of a lever in order to transform the
potential energy of a counterweight into kinetic
energy of a projectile. They were a staple of
warfare until the advent of gunpowder.
Your trebuchet should be able to launch a tennis
ball across the courtyard. You will build them at
home, outside of class, but will bring them to school
the day before for a practice run. Throughout the
construction process, you will need to take pictures
to document your work. You should have, at least,
four pictures, each member should be shown at
least once and the first picture should show the raw
There are a ton of videos online detailing how you
can make a trebuchet, but they all come down to
the same basic premise. The release mechanism is
always the hardest thing to make and requires a lot
of trial and error so do not wait to get started.
There is a certain type of trebuchet called a
Whipper Trebuchet that always gets the best
results. These are a bit trickier to build, but they
always yield the greatest results and the crowd
tends to like them more.
This video discusses some tips to make your
trebuchet shoot further. Here is a video where a
person makes a simple trebuchet from start to
finish and discusses some of his rationale.
AP Physics C / Honors Physics
Trebuchet Project
Grading Rubric
● Timesheet
■ 10 points - The timesheet is well-documented and is turned in on time.
● Images
■ 2 points - Each member of the group is shown in at least one of the images.
■ 2 points - One of the images shows the raw materials before construction has begun.
■ 2 points - One of the images shows the finished product.
■ 4 points - There are at least four images.
● Measurements (3 points possible)
○ 3 - All measurements are shown and units are included on all measurements.
○ 2 - One or two measurements are missing or don't have units.
○ 1 - Three or four measurements are missing.
○ 0 - More than four measurements are missing.
● Views (4 points possible)
○ 4 - Two views of the trebuchet are shown and are carefully depicted in the drawing.
○ 2 - Only one view of the trebuchet is shown or one of the two views is very sloppy.
● Format (3 points possible)
○ 3 - Image is done in Google Drawing or some other digital platform.
○ 2 - Image is hand-drawn, but shows effort and attention to detail.
○ 1 - Image is hand-drawn, but doesn't show much effort or attention to detail.
● Durability (20 points possible)
➢ Survives each of the four launches (5 points each)
● Distance (10 points)
○ 10 - Best launch range is four times the long arm.
○ 7 - Best launch range is three times the long arm.
○ 4 - Best launch range is two times the long arm.
○ 1 - Best launch range is equal to the long arm.
○ 0 - Ball doesn’t launch.
● Clean-Up (20 points)
○ 20 - Trebuchet station is completely cleaned and the trebuchet is removed on the day of
Medieval Fest.
○ 10 - Trebuchet is not removed by the end of the day, but a plan is in place to remove it.
○ 0 - Trebuchet is not removed and a plan has not been communicated about its removal.
● Peer Evaluations (10 points)
➢ Average of group mates’ confidential evaluations of you.
● Calculations (10 points)
➢ Score from completed calculations page.