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Ratios and Data 6-8 / Week 08 / Wednesday
3/6
Week 08 · Multiplying and Dividing Signed Numbers

Wednesday

Numbers Lab: paper ball toss
// Repeated hops and the sign rules
⏱ about 20 min

Wednesday: Numbers Lab, Paper Ball Toss

Rocket sets a bowl on the floor and tapes a line two big steps away. "Paper ball toss. Five throws each."

"A hit is +3 points," Raven says, writing the rules. "A miss is -2. Nova keeps score."

Rocket throws five crumpled paper balls. Three land in the bowl. Two bounce out.

"Three hits and two misses," Nova says, her light flicking between the bowl and the floor. "What is the total?"

"3 × 3 is 9," Rocket says. "And 2 × (-2) is -4. So 9 + (-4) = 5."

Raven takes her turn and gets one hit. "What do you notice about my score?" she asks, laughing.

"1 × 3 + 4 × (-2)," Rocket says. "That is 3 - 8. You got -5. Sorry."

"Write it all down," Nova says. "Every round is a number sentence."

What you need

  • Five or more paper balls made from crumpled scrap paper.
  • A bowl, basket or box as the target.
  • Masking tape for a throwing line, about two big steps from the bowl.
  • Your Numbers Notebook and a pencil for the score table.
Safety first
Use soft crumpled paper only, never anything hard. Throw at the bowl, never toward a person.
A grown-up picks a cleared spot away from breakable things, screens and lights.
Pick up every paper ball when you finish so no one slips on them.

Play and score

  1. Stand behind the tape line. Throw five paper balls, one at a time, at the bowl.
  2. Count the hits (in the bowl) and the misses (anywhere else). Hits and misses add to 5.
  3. Each hit is worth +3 points. Each miss is worth -2 points.
  4. Write the round as a number sentence: hits × 3 + misses × (-2). Work out the total.
  5. Play at least four rounds each. Record every round in your table.

The crew's rounds

Here are the crew's rounds from the hallway. The last total is left for you.

PlayerHitsMissesNumber sentenceTotal
Rocket323 × 3 + 2 × (-2)+5
Raven141 × 3 + 4 × (-2)-5
Practice round232 × 3 + 3 × (-2)?
SCORE THE ROUNDS
  • Read the question.
  • Tap your answer.
Rocket: 3 hits and 2 misses. What is his total?
Raven: 1 hit and 4 misses. What is her total?
The practice round: 2 hits and 3 misses. What is the total?
ROUND QUESTIONS
  • Read the question.
  • Tap your answer.
A round with five misses and no hits. What is the total?
A perfect round, five hits. What is the total?
A round scored -10 with no hits. How many misses was that?
A round has 0 hits and 5 misses. Each miss is -2. What is the total? Type the number with its sign.
WHY THIS EXERCISEThe worst possible round is a quick check that your sign rule is working.
Draw your score table for four rounds. Beside it, draw the hops for your lowest round on a number line.

Great lab work. Tomorrow you read the Field Day sign-up sheet, where fractions turn into decimals.

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