Mathematics Common Core

November 4, 2011

Last Session

Eight Standards of Mathematical Practice

1. Make sense of problems and persevere in solving them.2. Reason abstractly and quantitatively.3. Construct viable arguments and critique the reasoning of

others.4. Model with mathematics.5. Use appropriate tools strategically.6. Attend to precision.7. Look for and make use of structure.8. Look for and express regularity in repeated reasoning.

Today’s Session

•Learn about the format, tools and processes that will be used during math instruction in Howard County through engagement in problem solving activities. •Use hands-on materials in order to examine the elements of worthwhile mathematical tasks

The Locker Problem• There are 20 lockers in one hallway of your school. Each locker is closed and

numbered in order from 1 to 20.

• When the 20 students in Mrs. Dye’s class returned from summer break, the class decided to play a game.

• The first student ran down the row of lockers and opened every door.

• The second student started with locker 2 and closed every other door.

• The third students started with locker 3 and changed the state of every third locker.

• The fourth students started with locker 4 and changed the state of every fourth locker.

• The students continued this pattern until all 20 students had a turn.

– At the end, which lockers will be open and which will be closed?

– Which lockers have been switched the most often?

– How many lockers, and which ones, were touched exactly five times?

–What if there were 100 lockers? 500? 1000?

Which standard did you use?

1. Make sense of problems and persevere in solving them.

2. Reason abstractly and quantitatively.3. Construct viable arguments and critique the

reasoning of others.4. Model with mathematics.5. Use appropriate tools strategically.6. Attend to precision.7. Look for and make use of structure.8. Look for and express regularity in repeated

reasoning.