Control Blocks

Control blocks are used to control scripts under certain conditions.

What control blocks are?

Control blocks are used to control scripts under certain conditions. Example if a child get time-out, he/she is removed from all the fun activities for certain time (10minutes or 30 minutes). Here the child is controlled by the condition 10 minutes.

In Scratch we have 11 control blocks. Most of them are stack blocks.

Here we are not going to learn all the control blocks. Some are advanced (If Then, If Then Else) and not easy to understand for age group 7 to 8. Those control blocks will be explained in Level 2 book.

How to use “wait () seconds” block?

This block allows the scripts to run after certain amount of time. We use this block in stories.

Below is the example how wait block controls the conversation between two characters.

How to use “repeat ()” block?

This block allows to repeat the scripts for given number of times. Same script will run again and again for the given number of times.

How to use “forever” block?

This block allows to run the scripts for ever and never stop (Except you use the block stop all or stop this script).

How to use “if () then” block?

This block allows to trigger an action only when the given condition is satisfied/ true.

How to use “if () then, else” block?

This block allows to execute the instructions held under if when the condition is true. If the condition is false, the instruction held under else get execute.

How to use “wait until ()” block?

This block allows to wait until the given condition is true. If the condition is true, the instruction under this block get execute.

How to use “repeat until ()” block?

This block allows to repeat the code held under until the condition become true. If the condition true stop repeating the code held under this block.