Engineers are amazing because they solve all kinds of problems, big and small. You might think of engineers tackling huge challenges like building bridges, but they also help with everyday problems. One important step in the engineering process is testing solutions, and engineers always have a plan for this. Let’s explore how they do it!
Imagine you have a problem to solve, like knocking down a pile of marshmallows with a slingshot. You can change two things, called variables, to try and hit the target: how hard you pull the slingshot and the angle you aim it. At first, you might guess both and miss the marshmallows completely. This is where testing comes in!
To figure out what works, you should only change one variable at a time. This is called isolating a variable. By changing just one thing, you can see exactly what makes the solution work or not. In our marshmallow game, we changed the angle of the slingshot while keeping the pull the same. This time, we hit the target!
When testing solutions, engineers set criteria, or rules, to decide if a solution is successful. For our marshmallow game, success meant knocking over all the marshmallows in one shot. Let’s try this in another game: bowling!
In bowling, the criteria for success are knocking down all the pins in one turn, which is called a strike. You can change variables like how hard you throw the ball, the angle, and the weight of the ball. But remember, only change one variable at a time to see what works best.
To isolate a variable, like the angle of the throw, you need to keep everything else the same. Use the same ball to keep the weight constant. Keeping the speed the same is trickier. You could try throwing the ball the same way each time, but that’s hard to do perfectly.
Instead, you can use a ball ramp. By placing the ball on the ramp each time, gravity does the work, and the speed stays the same. This way, you can focus on changing just the angle to see how it affects your success.
By setting criteria and isolating variables, engineers can thoroughly test their solutions. If a solution meets the criteria, it might be on its way to being a big success. Next time, we’ll see how engineers change variables between trials to test solutions even more effectively!
Marshmallow Slingshot Experiment: Create your own marshmallow slingshot at home! Use a spoon as the slingshot and marshmallows as the targets. Try to knock down a stack of marshmallows by changing one variable at a time. First, change the angle of the spoon while keeping the force the same. Then, try changing the force while keeping the angle the same. Which method works best for you? Discuss with your friends or family why isolating one variable helps in finding the best solution.
Bowling at Home: Set up a mini bowling alley using empty plastic bottles as pins and a small ball. Try to get a strike by changing only one variable at a time. You can change the angle of your throw or the force you use. Keep track of how many pins you knock down each time. Which variable change helps you get the most strikes? Talk about how this relates to the engineering process of testing solutions.
Design Your Own Game: Think of a simple game you can create at home, like a paper airplane contest or a marble run. Decide on the criteria for success and identify the variables you can change. Try changing one variable at a time to see how it affects the outcome. Share your game with friends or family and explain how you used the engineering process to test your solutions.
