This activity is a fun way to practice mental math skills using kids' knowledge of Base-10. Use it as a math center or station, for practice or review, or even as an assessment. The pizza theme is sure to be a hit!
Students must use their knowledge of place value and Base-10 to determine the missing subtrahend--a multiple of 10 or 100--from a 3-digit minuend. Younger kids love algebra and feel brilliant when they are successful!
Make a copy of the recording sheet for each child.
Make one copy of the equation pages, cut them apart, and tape them around the room.
Have the students place their recording sheet on a clipboard or other portable hard surface.
Students move around the room to mentally determine the answer to each problem and record it on their sheet.
Both color and black and white versions are included.
Common Core State Standards
CCSS.MATH.CONTENT.2.NBT.B.7 Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
CCSS.MATH.CONTENT.2.NBT.B.8 Mentally add 10 or 100 to a given number 100-900, and mentally subtract 10 or 100 from a given number 100-900.
CCSS.MATH.CONTENT.3.NBT.A.2 Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.