STEM Critical Thinking Questions

STEM critical thinking questions focus on:

Here are 50 STEM critical thinking questions for middle school students, categorized by the areas listed above:

1. Quantitative Reasoning (15 Questions)

  1. A cookie recipe calls for 2/3 cup of sugar. If you decide to make 1.5 times the amount of cookies, how much sugar will you need?
  2. Marcus earned $18.50 from mowing lawns last week and $25.25 this week. He wants to buy a video game that costs $45.00. How much more money does he need?
  3. A train travels at a steady speed of 70 miles per hour. How far will it go in 3 hours and 15 minutes?
  4. A jacket is priced at $30. If there's a 15% discount, what is the new price of the jacket?
  5. The temperature was -3°C in the morning and rose to 10°C by the afternoon. What was the total temperature increase?
  6. You have a bag containing 10 red, 6 blue, and 4 green marbles. What is the likelihood of randomly picking a red marble?
  7. A rectangular playground is 12 meters long and 7 meters wide. If you want to put a fence around it, how much fencing material will you need?
  8. If 4 pens cost $2.20, how much would 9 pens cost?
  9. A bus departs from Station X at 8:30 AM and arrives at Station Y at 12:45 PM. If the distance between the stations is 250 miles, what was the bus's average speed?
  10. On a map, 1 inch represents 75 miles. If two towns are 4.2 inches apart on the map, what is the actual distance between them?
  11. You are mixing paint. The ratio of blue paint to yellow paint is 2:5. If you use 4 cups of blue paint, how much yellow paint do you need?
  12. A pie is cut into 10 equal slices. If you eat 3/5 of the pie, how many slices did you consume?
  13. The average score of 4 students on a test was 85. When a fifth student took the test, the new average for all 5 students became 88. What was the fifth student's score?
  14. A factory manufactures 200 toys per hour. If they operate for 7 hours a day, 6 days a week, how many toys do they produce in a week?
  15. You have $60 to spend at the grocery store. You spent $15.25 on meat, $20.50 on snacks, and $9.75 on drinks. How much money do you have remaining?

2. Scientific Reasoning (15 Questions)

  1. You notice that different types of soil affect how quickly seeds sprout. Design a simple investigation to determine which soil type is best for seed germination. What factors would you keep the same?
  2. Why does a boat float on water, but a small rock sinks? Explain your answer using the concept of buoyancy.
  3. A scientist is testing a new medication. They give the medication to one group of patients and a sugar pill (placebo) to another group. What is the scientific purpose of giving the sugar pill?
  4. When you mix baking soda and lemon juice, you see bubbles forming. What does this observation suggest is occurring? What kind of change is it?
  5. Why is it essential for scientists to document their procedures and share their findings with others?
  6. You place a metal spoon into a hot cup of tea, and the spoon quickly gets warm. What method of heat transfer is at play here?
  7. A student wants to find out which brand of paper towel can absorb the most liquid. Describe how they could set up a fair experiment to test this.
  8. What causes the Earth to experience day and night?
  9. You observe that a puddle of water on the sidewalk disappears on a sunny day. What scientific process accounts for the puddle vanishing?
  10. If you dissolve salt in water, is this an example of a physical change or a chemical change? Justify your answer.
  11. Distinguish between an observation and an inference. Provide a real-world example for each.
  12. Why is wearing personal protective equipment (like gloves or safety glasses) crucial when performing science experiments?
  13. You shine a laser pointer at a mirror, and the light bounces off at an angle. What scientific principle does this demonstrate?
  14. How would a researcher determine if a new fertilizer truly helps plants grow taller? What would they need to compare?
  15. Explain why objects fall towards the Earth when dropped.

3. Logical Problem Solving (10 Questions)

  1. If all cats are mammals, and all mammals are animals, then can you definitively say that all cats are animals? Explain your reasoning.
  2. You are in a room with three light switches, but only one turns on the light bulb in an adjacent, windowless room. You can enter the light bulb room only once. How can you figure out which switch controls the light?
  3. A person is on one side of a river, and their pet is on the other. The person calls their pet, who immediately crosses the river without using a bridge, a boat, or getting wet. How did the pet cross?
  4. You have an 8-liter container and a 3-liter container. How can you accurately measure exactly 7 liters of water using only these two containers?
  5. What number comes next in the sequence: 3, 9, 27, 81, \_\_\_? Describe the pattern.
  6. Consider this group of items: PINEAPPLE, ORANGE, POTATO, LEMON. Which item does not fit with the others, and why?
  7. A forensic scientist found tire tracks at a scene that showed a distinct pattern: front, back, front, back. What can the scientist deduce about the vehicle that made these tracks?
  8. Three friends, Emily, David, and Frank, each have a favorite fruit: apple, pear, or grape. Emily likes apples. David does not like pears. Which fruit does Frank like?
  9. You have a set of 12 identical-looking coins, but one coin is either slightly heavier or slightly lighter than the rest. Using a balance scale, how can you find the odd coin and determine if it's heavier or lighter in a minimum number of weighings?
  10. A sign at a library states: "All books on the top shelf are non-fiction" and "Some books on the middle shelf are biographies." Based on this information, can you conclude that "all biographies are on the middle shelf"? Justify your answer.

4. Spatial and Visual Thinking (10 Questions)

  1. Imagine a pyramid with a square base. If you were to flatten it out (unfold it) into a 2D shape, what shapes would you see?
  2. You are viewing a sculpture from the left side. If you were to walk around and view it from the right side, how might its appearance change?
  3. If you rotate a regular pentagon by 72 degrees clockwise, what would its orientation look like compared to its original position?
  4. Draw a simple house. Now, imagine you are hovering directly above the house and draw what it would look like from that aerial view.
  5. If you have a cylindrical block of wood and make one straight cut through it, what are some possible 2D shapes of the cross-sections you could create?
  6. Provide step-by-step directions from the entrance of your school building to the cafeteria, using only cardinal directions (North, South, East, West).
  7. Imagine an analog clock. If the minute hand is pointing at the 6 and the hour hand is pointing between the 10 and the 11, approximately what time is it?
  8. Which of these 2D shapes always possesses line symmetry: a parallelogram, an isosceles trapezoid, a scalene triangle?
  9. You are stacking shapes: a sphere on top of a cube, and then a cone on top of the sphere. Draw a sketch of this stack as seen from the front.
  10. If you are facing East, and you turn 135 degrees to your left, what direction are you now facing?

Free Resources

Cambridge Thinking Skills: Critical Thinking and Problem Solving (Second Edition)