Surf for More Math
Lesson 10 – Choosing a Calculation Method
To encourage your child to have fun on the Web while learning about Choosing a Calculation Method, here are some games and interactive activities they can do on their own or in pairs.
Goal
Choose the best way to add or subtract.
Builds Upon
Student Book page 162
Instructions for Use
Interactive Calculator allows your child to practice a method to add or subtract.
To use the Interactive Calculator, start by pressing any number. This number will appear in the window. Press the ‘+’ button or the ‘-’ button on the calculator, the number selected becomes shaded on the hundreds board. Add or subtract numbers. Press the ‘=’ button on the calculator to show the answer.
Estimating Differences lets your child practice a method of estimating the difference of 2 numbers.
To use Estimating Differences, click the ‘Start Subtraction’ button and read the equation in the text fields. Have your child click the button to indicate if the answer is correct.
Estimating Sums lets your child practice a method of estimating the sums of 2 numbers.
To use Estimating Sums, click the ‘Start’ button and read the equation in the text fields. Have your child input the estimation for the given equation. Click the ‘Check” button to indicate if your child has the correct answer.
