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Projects & Challenges for
Project based learning (PBL) &
Challenge based learning (CBL)

Challenges for science, engineering, math, and logic

Being intelligent is not having some magic formula which one can apply to every problem. It is, rather, having a number of ideas and not being as much in love with one that it cannot be dropped for another.


This article includes three areas:

  1. A discussion of challenges, problems, discrepant events, and similar activities.
  2. Explores instructional designs and characteristics for the labels of CBL and PBL, commonly used with challenges, discrepant events, problems, and projects, along with supporting research.
  3. Includes a list of 70+ challenges and questions and ideas to explore or investigate.

Challenges, problems, & discrepant events

Problem is a situation where the solution isn't readily apparent to the person with the problem.

Challenges are problems, activities, and tasks that require a solution that is novel, for the person, who accepts the challenge. Usually challenges are thought of as solvable, whereas discrepant events are characterized as illogical or unclear.

Discrepant events are perceived as illogical or not possible. They differ from challenges, which are usually thought of as solvable.

Project can be initiated as any of the above. The major difference is that projects usually have a duration beyond a few days. The units in the science investigations like the stream, rivers, & watersheds unit is representative of the depth of participation for a learner in a project. However, the format of the unit shouldn't imply that the instructional method of project learning needs to always be teacher directed with a learning cycle.

Instructional designs

If we want self-directed learners in the upper grades, we need to show them how to be self-directed learners in the primary grades.

Related philosophical ideas for CBL & PBL

Learning experiences presented as challenges, open-ended tasks, and projects:

  • Allow teachers and learners to live each day being curious and thoughtful about what is important in the world and life.
  • Allow active learning by doing.
  • Are rooted in purposeful and authentic experiences.
  • Provides a need and reason to know.
  • Pushes learners to consider the accuracy of their observations and sources.
  • Let learners drive their own learning.
  • Allows student inquiry.
  • Allows self-discovery.
  • Provides investigations learners care about.
  • Empowers learners to share their learning.
  • Fosters decision making, critical thinking, problem solving, analytical skills, and self-efficacy.
  • Are motivational.
  • Relates to teaching and learning standards.
  • Can be teacher direct, when learners ask for help or need essential information to progress.
  • Allows more opportunities to connect knowledge, skills, and dispositions to learning and the real world.
  • Provides more opportunities to integrate knowledge across content areas and for an integrated curriculum.

Notable labels for these instructional designs, include:

  1. Challenge-Based-Learning (CBL),
  2. Problem-Based-Learning (PBL), and
  3. Project Based-Learning (PBL)

Quick explanation of these three examples.


  1. Has a problem, question, challenge, situation, or activity.
  2. Requires a solution, tool, product, strategy/technology, method, or activity. And
  3. Produces a result, end, product, end condition, change to or learning outcome.

The time period of each varies depending on how the problem, challenge, situation, activity, investigation is framed. And the depth of investigation of each problem, challenge, situation, or activity will vary depending on how it is described.

Summary of each.

  1. Problem-Based-Learning (PBL) is when a problem is presented, which can be given or created by the teacher, student, groups, or class. As such the solution and result are usually less well defined.
    • Health problem when symptoms are known and the result is to relieve the symptoms and the treatment would be the solution. Fairly open assignment.
  2. Project Based-Learning (PBL) is usually when a person, group, or class works to create a result. The result can be a narrow closed product or an open comprehensive product. Projects can be created by the teacher, student, groups, or class.
    • Teacher assigns students to create a filter to filter sediment from water. The filter is the solution fairly open and clear water is the result. Fairly closed assignment. The project could be more open it ...
    • Teacher assigns or a learner decides to [create a technology (solution/product) to make clean water (result)] [problem]. This is more open, than the previous example, since a technology other than a filter can be used as the solution.
    • A learner decides to or a teacher assigns an exploration of the properties of water or liquids. A teacher plan to provide resources as needed might look like this.
  3. Challenge-Based-Learning (CBL) is when a person works to create a result or solution when given a problem or required result.


Rigorous PBL improves learning.

  • Second grade students in PBL social studies and literacy curriculum showed 5-6 months gains in social studies and 2-3 months in reading better than control group.
  • Third grade students in interdisciplinary PBL performed 8% better than traditional classes on key science assessments.
  • Middle level PBL students outperformed non PBL students on science assessments by 8%.
  • PBL in advanced placement courses increased scores on AP test by 8% in the first year and 10% after a second year of PBL
  • Positive achievement gains held across racial, ethnic, and socio-economic groups, reading ability levels, and with low-income families.


Seventy+ Ideas for challenges, problems, projects ...

  1. Use a 10 centimeter square piece of aluminum foil and create a boat that will hold the greatest amount of weight. Make a boat, float it, add weight (pennies) one at a time until it sinks.
  2. Soundproof a cardboard box. Materials: cardboard box (may want to put size restrictions), alarm clock or radio with a fine volume control or remote control which can be controlled from outside the box.
  3. Design three ways to measure the strength of a sheet of paper.
  4. Create a pendulum that swings sixty times in one minute.
  5. Use a piece of paper (8.5 X 11 inches), 15 cm of string, one rubber band, and 5 cm of masking tape and make a link for a chain. Use clothesline to tie each (student made) link to a tug-of-war line and pull until one breaks, record, pull till another breaks, record, and so on until all, except the last one, have broken.
  6. Use a birthday candle to heat water 10 degrees. How can the same amount of water be heated 50 degrees by using less candle? Materials: birthday candles, matches, test tubes, test tube holders, and thermometers.
  7. Use a toothpaste pump and make it pump something. Materials: wire or stick to push plunger from toothpaste tube (coat hanger or dowel rod the diameter of a coat hanger), toothpaste pumps, water, buckets, and flour.
  8. Create and/or solve circuit puzzle boxes. Materials: small boxes, wire, brass fasteners or small nuts and bolts, battery and bulbs to test the circuits.
  9. Paste or tape a magnet or magnets into a box. Seal and challenge students to guess what is inside. Older students can be challenged to find the shape of the magnet and the orientation of the magnetic field.
  10. Put objects into paper bags, socks, or legs containers. Challenge students to identify the objects. Could have pairs of objects and challenge the students to match the pairs by sound.
  11. Use dice to play ring around the roses.

    Rings around roses: 1-6!

  12. Aunt Molly. Challenge to discover what Aunt Molly likes and doesn't like by stating what she likes and doesn't like. Examples:
    • Aunt Molly likes yellow but she doesn’t like blue.
    • She likes green but she doesn’t like orange.
    • She likes the moon but she doesn’t like Mars.
    • She really likes beets, lettuce, cabbage, and greens, but she doesn't like vegetables.
  13. Nine squares. Make a 3x3 grid of squares for a total of nine, then put numbers in each square so that the total sum of three numbers horizontally, vertically, and diagonally is equal. For example place one of the numbers 1-9 in each square so the sums are equal to fifteen. Also available are puzzles with nine square pieces to assemble. Also nine dots in a 3x3 grid and challenge to connect all nine dots with four straight lines.
  14. Five square group challenge teams are challenged to build five different squares of the same size from the provided puzzle pieces without talking or taking.
  15. Can you use a syringe to remove water from a glass inverted in a container of water. Container inverted in water
  16. Hand out a sheet of paper and ask the student to walk through it.
  17. Give the students a picture of some objects like planets and moons and ask if they can calculate the size of one from the other. Or a picture of Michael Jordan dunking a basketball and ask them to calculate how high he jumped.
  18. Can you spin an egg? Does a raw egg spin different than a hard boiled egg?
  19. Can you stand an egg on its end? Can an egg be balanced on any day or only on the first day of spring (the vernal equinox) or the first day of fall (autumnal equinox) or is on the winter and summer solstice? Does it make a difference if it is raw or hard boiled?
  20. Can you drop an egg from the top of the school and have it not crack-up.
  21. Have students build a car with an egg as the passenger. Release it at the top of a ramp and run it into a brick wall. Can they design safety feature so the egg will survive the crash? Safety belts or straps, air bags, break away cars.
  22. Can you balance a pencil on the tip of your finger for a minute? Balance & stability activities
  23. Build an electric circuit with two switches so that one switch will turn on an electric light if the other is off, one will turn off the light if the other is off, and neither will turn off the light if the other is on.
  24. Build an electric circuit so that either switch will turn on or off the electric light no matter the position of the other switch.
  25. Build a sturdy bridge. Provide students with a limited amount of materials. Example 100 plastic straws, 10 yards of thread, 100 staples or 100 pins, one sheet 12x18 oak tag. The group that builds a bridge that spans 12 inches between two desks and holds the most weight is the winner.
  26. Build a sturdy tower. Give each group 50 straws and 100 pins (or 50 cm masking tape) and which ever group builds a tower at least 12 inches tall and holds the most weight is the winner.
  27. Build a tall tower. Give each group 50 straws and 100 pins (or 50 cm masking tape). Which group that builds the tallest tower wins. Probably need to go to a gym or other place with high ceilings.
  28. Solar box challenge. Have students build a box that will be placed out doors during the day for the designated time during a sunny afternoon. Provide each student with a thermometer and have them place it into their box. The box with the highest temperature reading is the winner. Or the winner could be the one that stays above room temperature the longest after they are returned to the classroom.
  29. Ice cube melt. Give each student a plastic bag and an ice cube. The student with the most water in the bag at the end of 10 minutes is the winner.
  30. What is the greatest weight you can support with a 4X6 index card?
  31. Can you lift your teacher?
  32. Can you make a thermometer?
  33. Can you make an alarm system that will be set-off when a person breaks into a container?
  34. Balance a nickel on a table with a paper match balanced on top of it. Then place a plastic cup over both of these. Can you knock the match off the nickel without knocking the nickel over.
  35. Can you float a cork in a glass of water so that it does not float to the side of the glass?
  36. What is the tallest free standing structure you can make using only playing cards and masking tape?
  37. Build as complicated a structure inside a clear plastic two liter bottle without cutting the bottle or altering the bottle in any manner. Entry is only allowed through the original hole at the top of the bottle.
  38. Ice preservation challenge. Have each learner make a device that will preserve ice. Limit the materials and resources they may use. At the start of the challenge provide learners with a plastic vial of ice. Have them place the vial into their device. The learner that has the most ice left at the end of the designated time is the winner. Insulation and energy transfer.
  39. Use two Popsicle sticks and make a bird’s beak which will get seed from the food source? Food source and seed is a plastic vial with a marble in it. Or more complicated use the following materials to make a beak to harvest a variety of foods from different locations. Materials: 2 paper clips, 2 Popsicle sticks, 1 clothes pin, 2-15 cm strips of masking tape. Food sources: 1. 5 cm piece of plastic straw or coffee stir set flat on a table. 2. Large marble on the top of a table able to roll. 3. Penny flat on the table. 4. 7 cm piece of string flat on the table. 5. Large marble at the bottom of a plastic medicine vial.
  40. Hot water keeper. Give each person 100 ml of 100 degree water, place it into their container, time for 15 minutes, hottest after 15 minutes is the winner, or put thermometers in each, record the temperature every minute for 15 minutes, and the winner is the one with a graph that has the smallest slope.
  41. Make an object that when put into a container of water, it will sink, stay sunk for at least 10 seconds, then rise to the top, and float there a minute.
  42. Airplane flying challenge. All students are given the same design and the furthest flight wins, or longest in air. Or the students are given the same design and are allowed to add any number of paper clips they desire. Or they are allowed to use any design they choose for their plane, but limit the materials.
  43. Balloon race. Put a string across the room and each person gets a straw, balloon, 3x5 cards, and tape. The rocket that moves the furthest on the string wins.
  44. One hundred gram motorized lift challenge. Give each student or group an electric motor and allow them to design and bring materials for a device to lift 100 grams.
  45. Parachute. Make a parachute that is less than 24 inches in diameter. Add 5 grams, drop from a high place, time, the one that takes the longest to hit the ground wins.
  46. Tin can derby. Use a coffee can, washers, lids, rubber band, and washers to make an object that can roll across the floor by itself. The furthest roll wins, or the straightest.

    Coffee can roller

  47. Seed to seed. The first person to grow a plant from a seed, plant a seed from that plant, and have it germinate wins.
  48. Grow the tallest plant in 10 days.
  49. Plants alive. The person(s) that can keep a plant alive all year wins.
  50. Locust tree germinator. The first person to germinate a Locust tree seed wins.
  51. Water filter. Construct a filter that cleans dirty water. May want to limit materials and size of filter. Give each person one cup of dirty water, the water with the best clarity wins.
  52. Design a creature that could live on another planet.
  53. Catapult. Build a catapult. The one that launches the teacher’s rock the farthest wins.
  54. Bubble contest. Make the largest, smallest, most, fewest, different shapes, (JOY). Use an overhead projector and a needle to find where on the surface of a bubble is the weakest.
  55. Design a way to measure the brightness of light bulbs.
  56. Density of liquids. Make a hydrometer from straws, clay, and BB’s. Use it to order liquids of different densities.
  57. Strongest electromagnet. Give each student the same amount of materials: wire, battery, and metals. Use paper clips or other objects to test the strength.
  58. Use a pan balance to arrange x amount of objects in order by mass.
  59. Use a pan balance and 12 objects with all but one having the same mass. Determine which one is different in three weighings or less. Make up mass problems of your own.
  60. Using a five and four liter bucket, how can you measure two liters? Using a four and three liters bucket, how can you measure two liters? Make up others of your own. Other bucket problems.
  61. Get a grow toy and challenge students to find how much it grows or how much water it will absorb.
  62. Balance 6 common nails on a pencil.
  63. Paper towel sucker-up contest. Design a paper towel to soak-up the most water. Must be smaller than 10 cm X 10 cm X 2 cm.
  64. Use a candle, a block of wood, and copper tubing to build a steam engine boat.
  65. image 13
  66. Use the materials to lift the student? Materials: Plastic bag, air pump, duct tape, board, chair, student.
  67. Make a trap to capture a particular kind of insect (fly, cricket, cockroach) alive.
  68. Build a machine that counts.
  69. Select a food label and make a report that describes every word on the label.
  70. Make a list of simple machines. Identify ten of the most common tools in a shop and describe how each includes a simple machine.
  71. Create a magic demonstration that changes the color of a liquid and perform your act.
  72. Make a garden:
  73. Design a safe way to get to school in bad weather. Research how children get to school around the world and then designe a way to get to school in bad weather.
  74. Which is bigger? Select two bodies of water, lakes, rivers, sea, gulf, ocean.. and use their measurements and geometry to document reasoning for why you believe one is bigger than another. Decide how to measure: one dimension, length, width, height, or two dimensions - area, three dimensions volume or four? Time? …
    • Suggestions Lake Tahoe v. Flathead Lake. Sources
    • Rivers: Platte v. Missouri (to where the Platte enters it)
    • Four oceans: order from smallest to largest.
    • Two of the Great Lakes,

Questions and ideas to explore and investigate

Physical science related

  1. What is temperature? How do we know what is hot and cold? Why is measuring temperature important?

Life science related

  1. What is living?
  2. What is the smallest structure of life? What are the least number of systems a micro organism needs to live? Make a diagram of a micro organism. How does it compare to a cell? Is there a difference between plant and animal cells?
  3. What is a leaf? What are the different shapes of leaves? What is the advantage of a certain shape? Make a leaf collection. How are leaves classified? Why? How ar leaves connected to trees? How does the area of one leaf compare to another? See leaves in trees activities.

Earth science related

  1. What are rocks?
  2. What are stream, rivers, & watersheds?

History and social science

Project for the American Civil war and slavery

Need to select or create essential or focus questions for the project.

For example we could use our integrated curriculum framework's four contextual areas to create them. The table below includes the 14 sub areas for the four contextual areas (global, relationships, time, symbolic).

Contextual Areas → Global Relationship Time Symbolic
Contextual Areas subcategories
  1. Interdependence
  2. Sustainability
  3. Diversity
  4. Partnership
  5. Change
  6. Cycles
  7. Energy flows
  1. Individual and group relationships
  2. Individual views and responsible decisions and actions
  3. Collective community actions and decisions
  1. Past, present, and future orientation
  2. Consider changes through time for understanding, critical thinking, and decision making
  1. Information and knowledge is arranged by humans resulting in the same information meaning different things to different people
  2. Critical thinking with systematic approach using observations, ... for understanding and decision making based on quality.
Possible focus questions for the contextual areas
  1. How are the states of the united states interdependent?
  2. What were the advantages and disadvantages for sustaining one country?
  3. How did the idea of diversity change from before to after the war?
  4. What global partnerships or treaties among nations aided either side?
  5. What changes lead to agreements and disagreements?
  6. Cycles How did the relationship between public purposes relate to personal freedoms and private money interests affect the war?
  7. Energy How did the availability of resources, goods, and money, affect the war?










What were the kinds of individual, group, & community, decisions being made in different parts of the country that might have afffected the decisions being made?

Starting with 1775 and leading up to the start of the war; how did the political and judicial decisions made lead to increased conflict?

What outcomes were desired as a result of the war for someone from the north and someone from the south?


Use authentic resources: photographs, art, music, statistics, literature, speeches, books, essays, poetry, videos, ... to research and answer the 14 contextual area focus questions.

Then share what you discover and incorporate the information to create an informational picture book on the American Civil War and slavery.

Possible questions for a broader focus:

  1. Race in America today: what has changed since the civil war?
  2. What is the historical context of the civil war: timeline
  3. Geography of the Civil War
  4. Slavery: What caused the American Civil War?
  5. Slavery: History and daily life

May require mini lessons on necessary topics to provide information. Such as:

  • Economics, business, farming, industrialization differences in
  • Life in the northern and southern states.
  • Geography differences and effects on transportation of people, goods, and services.
  • How to use primary sources.
  • How to read informational texts.
  • How to interpret photographs and other visual information.
  • How to use research to tell a story.
  • How to create an informational picture book.
  • Time management skills.
  • Diagrams or flow charts with plans on how to set goals, plan, schedule, assess, and achieve goals.
  • Asking for help and accepting appropriate feedback.


See also discrepant events for challenges or problem solving short duration activities. Unless one is motivated for a deeper dive1!

Organizations with related resources:


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