In this app, the program voice tells the student (for instance) "Let's count by eights by clicking on the right numbers. We will start with number 8 and then add 8 each time." After the student gets to 80 (ten eights), the program voice will say "That's right. Now let's count by 8s. 8, 16, ...."SettingsPrompt(Blink)This is checked by default. If the student fails to find the correct answer within ten seconds, the program guides him/her to the correct choice by making the correct choice blink.Congratulatory AnimationThis box is checked by default. When this is checked, clicking the correct number invites a congratulatory animation. This animation runs for ten seconds. Click anywhere on the screen or press the space bar to stop the congratulatory animation.Count byThis chooses the number and intervals by which the "Count by ..." sequence is chosen.BackClick on the "Back" button to close "Counting By Twos, Threes, Etc" or return to the previous page.