Students estimate the whole-number locations of unlabeled points on number lines. Students make an initial estimate of a point’s location and then “zoom in” on an interval that contains the point. This magnified interval is divided into ten smaller equal parts, allowing students to refine their estimate. Students continue to magnify the number line until they can precisely locate the point. Challenges range from estimating the location of a point on a 0–100 number line to estimating the location of a point on a 0–100,000 number line.
(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; (5) Use appropriate tools strategically; (7) Look for and make use of structure.
4.NBT1, 2; 5.NBT1