Here ye, here ye: There are good things coming out of video games. Kids brains are quickly becoming wired to a new way of thinking, and it goes hand it hand with a time honored math strategy we call "guess and check."
Picture your beautiful blond-haired, blue-eyed 9 year old battling against an evil monster. Time after time her weapons are not strong enough and the character disappears from the screen. But magically, the character returns with one life gone, but ready to battle the same evil monster again and with new ideas for attack. In the end, your kind-hearted wonder either stops playing, completely looses all their lives or finds a way to defeat the evil villain.
Some math problems can be solved the same way, and we need to teach kids to harness their video game mentality and attack them like an evil villain. The guess and check math strategy requires a child to try out one possibility, check to see if it works, revise their attempt, check to see if it changes the outcome, and then continue to revise and check until the "answer" is achieved.
The hard part of the "guess and check" strategy is to keep kids persevering even when their guessing is wrong. We do not want kids to loose all their math lives or stop playing the math game. Video games have programmed kids to be okay with trying over and over again until they win, and now we need to re-program our students to keep going as well. Re-programming is key because students over the past 30 years have been taught that all math problems can be solved in "2 easy steps."
The classic guess and check question is:
Grandpa's farm has chickens and pigs. When Jenny went out to feed the animals she saw 80 feet but only 32 animals. How many animals were chickens and how many animals were pigs?
Here are some other "guess and check" questioning techniques:
- There are 24 kids in 3 grade with twice as many boys than girls. How many students are boys and how many are girls?
- How many different combinations of coins can you use to get 25 cents; fifty cents?
- List out a series of 6 numbers. Which two numbers can add up to 625? Which three numbers can add up to 625? Four numbers?
- Give all kids a geoboard and a set of specific descriptions of a shape (make a shape with 3 sets of parallel lines; make a 4-sided shape with one set of parallel lines). Students must continue to move the rubber band around until they have achieved a shape within the parameters. Walk around and continue to encourage students to check all descriptions before saying they are done.
- What is the longest perimeter of polygon that has an area of 25 square inches. In this activity, have students use grid paper or manipulate square tiles to determine their final answer.
- My favorite guess and check problem is Marilyn Burns Banquet Table question (link provided here). She also has a book Spaghetti and Meatballs for All to read aloud before completing the problem. http://mathsolutions.com/documents/0-590-94459-2_L.pdf
"Guess and check" has to be modeled by the teacher over and over until the teacher defeats the "being okay with my first idea" evil villain.
