P – EC – RT10

Terry and Reid estimated the number of people in line for concert tickets. Terry used a referents of 10 while Reid used a referent of 20. They estimated the same number of people. How is this possible if they used different...

P – EC – RT11

Jamie, Matty and Reid estimated how many balloons were at the party. Jamie used a referent of 10, Matty used a referent of 25 and Reid didn’t use a referent. All three of their estimates were very close. How could their estimates have been so close if they all...

P – EC – WP11

Students were asked to estimate how many cars were in the parking lot. Sammy said her estimate was 50. She used 5 as a referent, and skip counted by five 10 times. Sammy said there were about five cars in each row and there were about 10 rows. Is Sammy’s...

P – EC – WP12

Students were asked to estimate how many cars drove by the school during lunch. Marsha said her estimate was 20. She used 5 as a referent, and skip counted by five 4 times. Sammy said that five cars went by during the first 5 minutes of lunch and there were 20 minutes...

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