Destination Imagination Instant Challenges written by volunteers. 2006. BC Original Minds Association.
Tell students that they will be working in groups (of 2,3 or max 4) to build a long bridge between two chairs/a chair and desk, using the materials provided. The bridge can be as narrow as they wish (it can be for ants to cross on), but it must stay up off the ground. If you would rather not have the competitive nature of this challenge, make a scenario, such as "we will turn our classroom into a city with long bridges for ants to move between desks and chairs".
Students may only use the materials provided, and cannot get any additions/replacements. Materials can be opened up, torn or broken if the students wish.
Tell them to investigate and manipulate the materials to see their different properties and ways that they might be used. Some materials will be good for structural pieces, some will be good for fastening those pieces together, some could be used as either.
Hand out bags/trays of materials, or ask students to collect their own tray of materials from bins.
Allow 20 minutes or more for building.
Some creative ideas I have seen (pictured), usually overcoming the little amount of tape they are given (try the challenge with no tape??):
Using small pieces of pipe cleaner, or toothpicks or pieces of chopstick to attach pieces of paper together.
Opening the clothes peg wide so that it clamps onto a table edge, as well as to a piece of paper.
One end of the bridge simply sitting on a desk, using materials to keep it weighed down.
Part way through building, visit each others' bridges and ask each group present a challenge they encountered and how they overcame it, or to ask the rest of the class to help them solve it. Just as engineers share ideas to solve structural problems, students are encouraged to share ideas within and between groups.
Discussion points to bring up during sharing:
Each of the materials have different properties - some are flexible, some are strong (metals are strong and flexible, paper is light). Some can be broken apart to make them longer.
Doubling up of materials makes them stronger. This is also done in making real bridges e.g. several steel beams are strapped together to make a support.
A bridge needs two components: 1. structural pieces, which make up the scaffolding and give a bridge its length. Students may have used chopsticks, extended pipe cleaners or long pieces of paper, while the structural elements in real bridges are steel or wooden beams that are long and rigid. 2. fasteners hold the the structural elements together. Students might use bolting (e.g. weaving a toothpick through two pieces of paper), taping, or crimping (e.g. tightly wrapping a piece of pipcleaner around a chopstick or using a clothespin) - all these methods are used to make real bridges. Other methods used to fasten real bridge structures together are welding, gluing and cement. Some of the materials given to the students can only be used as structural pieces, some only as fasteners, and some as both. The students will find unanticipated ways of using the materials.
After the lesson is completed, optionally have students remake the kit bags for the next use of them.
Other ideas for building challenges, inspired by Destination Imagination challenges:
1. Build a structure as high as you can. Materials for each group: 15 sheet of paper.
2. Build a freestanding tower that is as tall as possible. Materials for each group (adapt if necessary): 10 toothpicks, 4 plastic spoons, 4 pieces of tape, 60cm string, 2 elastic bands, 6 paper clips, 2 paper cups, 2 pieces of paper, 4 chopsticks/pencils, 1 piece of foil, 4 straws.
3. Build a structure with a solid roof and at least one solid side, that one team member can get inside. Materials: 20 sheets of newspaper, 5 pieces of tape, 5 paperclips
4. Build a structure that will support as may marbles/weights as possible at lest 20cm above the table. Materials: 20 pieces of spaghetti, 3 straws, 4 toothpicks, 2cm length of clay, 2 paperclips. Scissors may be used but may not be part of the structure.
5. Build a structure that will withstand the wind from a fan. Materials: 2 paper plates, 2 sheets paper, 3 paper clips, 8 popsicle sticks, 2 pieces of tape
Lawson, Jennifer. 2001. Portage and Main Press (Peguis Publishers)
p.42 is the worksheet used for the activity listed.
Note on preparing the plastic strips: the plastic strips should be made from sturdy, flexible plastic sheets, such as a portfolio cover, plastic place mat, or thin plastic chopping board. They can be sliced with a paper cutter. Punch the holes with a small hole punch with a 3mm diameter (the holes of larger hole punches will allow too much wiggle in the shapes). It will take a while to make a class set.
Strips could also be made form thick paper, but they will not last as long.
Show students an image of a local bridge with a visible frame, and ask if they have seen or been over this bridge, or one like it. Tell them that the frame is strong and keeps the bridge rigid, even with the force of all the cars and trucks driving over it.
Show students an image of a frame of a house, and ask if they have seen anything like this on a construction site in their neighborhood. Tell them that behind the walls and under the roof of every building there is a frame like this one that supports the weight of the building and everything in it.
Point out the steel/wooden beams that make up the frame of the bridge/house. Tell students that these beams are fastened together in shapes that are strong, which can distribute and balance the forces on the structures, so that they do not fall down.
Explain to the students that they will be building their own regular polygons, from rods and fasteners, and testing them for strength, to find out which shapes are the sturdiest.
Show the students the rods and fasteners that they will work with (the short plastic strips and the brads), and demonstrate how to fasten the plastic strips together to make the outside of a shape (see photo 1), with three or more sides. Then demonstrate how to test the strength of their shape by laying a square on the table and gently pushing it from one side (see photo 2).
Distribute kits containing eight short plastic strips and eight brads to each student pair. Distribute one worksheet (attached below) to each student.
Students are instructed to make a triangle, a square, then any other simple polygons they like. The shapes should be a simple outline of a shape, with no cross bracing. (Students will be able to build up to an eight-sided octahedron with their kit.) Students should draw each shape in a box on their worksheet, name it if they can, and record the number of sides.
After testing it for strength, they also record on their worksheet how strong and sturdy it is compared to their other shapes (for example using a star system). Polygons that hold their shape well (typically the triangle) are recorded as being the most sturdy (e.g. three stars). Polygons that easily distort and lose their shape (most of the other shapes) are recorded as being the least sturdy (e.g. one star).
Students add the shapes they have built to a class chart, with names and number of sides, until all shapes built are listed for all to see.
Students are asked, pair by pair, which shape they built was the most sturdy, and how sturdy the other shapes were. Record the sturdiness next to the appropriate shape on the class chart. (Some students’ data may be different from others, as sometimes the brads are tight enough to restrict the movement of the plastic strips. However all results are valid, as they are what the students observed, and are added to the data. The outlier data points are not the majority so are not included in the discussion of class results.)
Summarize the class chart: the triangle should be the shape that most often has three stars. Other shapes will vary in their rankings, but should usually rank below the triangle.
Discuss why the triangle is the strongest shape: a triangle will hold its shape even when forces are applied to it from any direction. The shape of a triangle can only be changed by changing the length of its sides, so if its sides stay rigid (do not buckle) the triangle is stable. A force on a triangle is spread around the shape, as compression (pushing forces) and tension (pulling forces), and these forces are balanced. In comparison, a force on a square or other shape with more sides can change the shape by collapsing the corners.
Ask students how they might make the weak shapes stronger. If prompting is needed, ask them which was the strongest shape (triangle), then how this shape might be made within the weak shapes.
Distribute five long plastic strips to each student pair at their desks.
Ask students to make their original shapes, then add cross braces to reinforce the weak shapes and make them strong. Photos 3, 4 and 5 show some examples of the many possible outcomes.
Ask students to retest the reinforced shapes for strength, and look for the shapes (usually triangles) that have been made from the original, larger shape.
Students bring one of their reinforced shapes to a group discussion, and show the triangles that are within it. If there is any weakness in a shape still, ask students how this could be strengthened, and point out the additional triangles that are made.
Look again at the images of the bridge and building. Ask students to find the shapes within the frame, noticing that many or all of the shapes are triangles. Engineers have learned that triangles are strong shapes, so build them into any large structure to keep it rigid and strong.
This is really two activities, but they would always be used together, for a full lesson.
Show students ideas of mobiles.
Ask them to draw their mobile, probably best with just two sticks for time, and more interesting if one stick hangs from another so the balance point is not in the centre (see first photo).
For materials, thicker twines (e.g. hemp) and heavier objects (e.g. pine cones) allow students to do more of the tying themselves.
For hanging origami, embroidery thread can be stapled to the paper.
When they start to build it, students should work up from the bottom of the mobile.
First hang the materials to each end of the bottom stick, then hot glue in place.
Then attach the thread and move it sideways along the stick until this bottom stick is balanced (ask students to predict where the balance point will be if they have done activities on balance points and relative masses already). Then hot glue in place (with as little hot glue as possible so the balance is not upset).
Then attach the top of this thread to one side of the next stick up (or more centrally if the students prefer a more symmetrical mobile). Add (an)other object(s) to the end(s) of the stick. Tye the hanging thread and move it until the balance point is found, before hot-gluing in place.
See balanced hanging wire structure: Steven Caney's building book p.292
Mobile math: https://www.teachengineering.org/activities/view/cub_art_lesson01_activ…
Draw/write something on the piece of paper.
Place the drawing behind the card so that it is not visible.
Find the place to hold the mirror so that you can see around the card at your drawing.
Stick the drawing on the underside of a table.
Find the place to hold the mirror so that you can see under the desk at your drawing.
Play around with other ways of using the mirror to see around corners/behind you etc.
Make a periscope
To make the catapult arm:
Tape the short popsicle stick to the spoon handle, to reinforce it.
Lay the end of the spoon handle over a silver handle of the binder clip, and temporarily open up the binder clip, so you can tape them together tightly with duct tape.
Use a small loop of tape to secure the min cup cake holder in the scoop of the spoon - this makes a deeper bucket for the ammunition.
To attach the catapult arm:
Clip the spoon handle with its binder clip to one lip of the tin can, so that the catapult arm can swing up to the other side of the can.
Attach the second binder clip to the other side and the other end of the can.
Loop an elastic band over the scoop of the spoon, across the can, and behind the inside handle of the second binder clip. The catapult arm should be pulled up against the rim of the can.
One of each of the binder clip handles can be flipped back, to make the attachment more secure.
To fire the catapult:
Make ammunition from balls of aluminium foil.
Load the ammo in the bucket, while tilting the catapult backwards, so the ammo doesn't fall out.
Pull back the arm of the catapult by the reinforced handle, while moving the can back to its horizontal position.
Let the arm go. The ammunition should fly several metres.
(In the classroom students can fire the catapult without any ammunition, to understand how it works.)
Discuss the forces and energy transfers:
When you pull the arm back, energy is stored in the elastic band. As the arm is released, the elastic band contracts again, exerting a force on the catapult arm and pulling it forward again. The bucket of the catapult exerts a force on the ammunition, pushing it forward with it. When the arm hits the can, the ammunition has no force to stop it from moving, so it continues to project forward. Gravity pulls the ammo downwards as it moves, so it makes an arc across the room.
The catapult is a class 3 lever, with the effort (the elastic band pulling on the catapult arm) between the fulcrum (the binder clip hinge) and the load (the bucket). The bucket moves further than the spoon handle, but experiences less force at one time (though has plenty of force to move the ammo forward).
Discuss Newton's Laws in the catapult:
1st Law: Focus on the ammo - catapult arm makes it move. Gravity makes it fall. Air slows it down. The ground pushing up makes it stop.
2nd Law: F=ma. A greater force (stronger band/pulled back more) will make it go further. A larger mass will go less far.
3rd Law: At each step there is a force pushing back on the ammo, even when it is still. When one force is greater than the other, the ammo moves or slows down.
Take the students outside to fire their catapults.
Scrape out lines in a gravel field or chalk up concrete, to provide the students with metre marks from a firing line. Students can stand on the line and measure how far their ammo flies each time.
Change the forces:
Ask students how they can make their catapult fire further (also helps students that are having trouble). Ideas: make the elastic band stronger by doubling it up, or switch for a stronger elastic band. I use three elastic sizes, #32 to start with, then add in #16 and #64. The sizes do not matter, but these bands do work.
Graph the results:
Ask students to record their distances for each sized ammunition.
Graph the data, with students initialling their places on the graph (see photo).
Note that I have not been able to make any consistent pattern from graphing whole class distances, either from different sized balls or different elastic bands. Neither is there no clear correlation between the distances fired and different elastics when used by the same student with only a few data points.
It is still OK to graph and see that there is no distinct pattern - opportunity to ask what other variables there might be, and how to test for these. Also an opportunity to explain that sometimes we need more data to see if there are any patterns. I want to try students each graphing their own data - and collecting around 10 data points each. (I think they will also more naturally want to collect more data to find a pattern.)
If done outdoors in the cold/wet, tape the spoon to the popsicle stick for students beforehand.
Introduction:
I have seen this called a "viking catapult", based on how it is made up of rods lashed together.
The skewers model tree trunks, the elastic band models rope and animal sinews.
Procedure:
Clip the sharp tips off the bamboo skewers. Cut one of the skewers in half.
Refer to the image to see the final shape of the scaffold, and follow this order of construction if you like:
Use an elastic band to secure three skewers together at one end.
Use another elastic band to secure the other end of one of these skewers to two more skewers (at their end).
Take one free skewer end from each bundle, and bind them together - this should make a triangle.
Take the last free skewer end from each bundle, and bind them together - this should make a second triangle. The two triangles you just made have one skewer in common.
Hold the two triangles apart from each other and brace them open with the two short skewers, using elastic bands at each joint, as in the photo.
To make the ammunition pouch:
Loop an elastic band through each of the holes.
Two of these elastic bands can hook over the upright struts of the catapult.
The third elastic band should be secured to the bottom skewer with one or two half hitches.
Make ammunition from balls of aluminium foil.
Hold the ammo in the pouch as shown in the second photo, then release. It should go several metres.
Started this catapult in science club, but ran out of time. Too fiddly with the elastic band winding for grades 1 and 2.
Show students how to read their thermometer, making sure not to cover their hand over the bulb.
Students make temperature measurements at different places in the pond. They record each temperature measurement on correct location on the map.
Discussion: was there a change in the pond temperature?
We found the shady spots were a little lower in temperature.
If a thread is used to suspend the thermometer from a bridge, be very careful not to snag ducks, turtles or other wildlife. Better not to use a thread if possible.
Take the class to the pond.
Review the activities, and the pages of the worksheet (see attachment):
On the map, record temperature measurements where they are made; draw a pond invertebrate in the circle and point on the map to where you found it.
End with a scavenger hunt if there is time (we did not).