Catapult

The Catapult is an activity in JumpStart Math for Second Graders. It is designed to teach addition, subtraction, and place values at a second grade level.

Premise
Ratso has ordered his henchmen to build walls around the castle to keep help out. CJ and Edison must use the castle's catapult to break down the walls.

Description
An equation will appear on the wall. The catapult must be loaded with the number of stones that equals the answer to the equation. There are stones worth one each and boulders worth ten each. The catapult can hold up to three boulders and nine stones at a time. The mallet can be used to break one boulder into ten stones, and the glue can be used to combine ten stones into one boulder. When the correct number of stones has been loaded into the catapult, the player must click on CJ to launch the catapult. The activity is completed when all the walls have been destroyed.

Digital manual description
Ratso's henchmen have been building walls around the castle designed to keep help out. Luckily there's a catapult on top of a castle tower. Help CJ and Edison use the catapult to smash the walls. The catapult can hold up to three boulders (designating the "tens" position), and 9 stones (for the "ones" position). You can create more stones by smashing boulders, or, you can glue ten stones together to make one boulder. Hurry, though, because you must knock down the entire wall before Zombo, one of Ratso's henchman, can build it up six levels high.


 * Read the equation on the wall.
 * To make a boulder out of ten stones, click on the glue bottle.
 * To make ten stones out of one boulder, click on the mallet.
 * Load the catapult with the correct number of boulders (the tens place) and stones (the ones place) that will answer the equation.
 * Click on CJ so he can pull the catapult lever.
 * Knock down all existing walls to win the game.

SKILLS: Adding and subtracting with regrouping, place values 1s and 10s.

Trivia

 * This is the only game where you could lose automatically when the wall reaches 6 rows high