4th Grade Unit 2
Estimation and Computation
 Estimation Challenge

OBJECTIVE: To develop estimation strategies when finding an exact answer is impractical.
 Adding with Partial Sums, Methods for Addition

OBJECTIVE: To review place-value concepts and the use of the partial-sum and column-addition methods.
 Methods for Subtraction

OBJECTIVE: To review the trade-first and partial-difference method for subtraction.
 Addition and Subtraction Stories

OBJECTIVE: To review the use of mathematical models to solve number stories.
 Estimating Your Reaction Time

OBJECTIVE: To provide experiences with estimating reaction times and with using statistical landmarks to
describe experimental data.
 Describing Chances, A Thumbtack Experiment

OBJECTIVE: To review vocabulary associated with chance events and to introduce the Probability Meter.
 Magnitude Estimates for Addition, Subtraction, and Products

OBJECTIVE: To provide experiences with making and using magnitude estimates for products of multi-digit
numbers, including decimals.
 Multiplication of Whole Numbers and Decimals, Solving Number Stories

OBJECTIVE: To review the partial-product method for whole numbers and decimals.
 Lattice Practice, Multiplication by the Lattice Method

OBJECTIVE: To review and provide practice with the lattice method for multiplication of whole numbers and
decimals.
 Dividing by Powers of 10, Multiplying and Dividing Decimals by Powers of 10

OBJECTIVE: To apply student’s knowledge of multiplication and division using large numbers.
 Millions, Billions and Trillions

OBJECTIVE: To provide experience with comparing the relative sizes of 1 million, 1 billion, and 1 trillion and
using a sample to make an estimate.