Computing Lesson 3

Remember to link to Scratch https://scratch.mit.edu/projects/editor/?tutorial=getStarted

and open the file you have been editing from Week 1.

LO: I can control when objects need to be visible.

There are two parts to this lesson. The first is to introduce the blocks ‘show’ and ‘hide’.
These can be inserted into scripts for each character sprite to make them only appear visible when
active. Demonstrate by running and then viewing the code in the project ‘Haunted House 3a – Show and
Hide’. Can children spot what has been added to the code since last time (i.e. ‘show’ and ‘hide’ blocks)?

Can you correctly use the ‘show’ and ‘hide’ blocks to control visibility of sprites? Children
follow the instructions on the Activity Sheet.

The second part of the lesson introduces another use for the ‘show’ and ‘hide’ blocks.
This is when you can create a button to switch backdrops. Demonstrate using the next stage of the
project in ‘Haunted House 3b – New Backdrop’.

Discuss the other amendments required to make the project work properly
with a second backdrop, working towards the idea of animating a longer story rather than just one
scene. Deconstruct the code in the example Scratch project (look at what new blocks have been
inserted and what changes have been made). This includes: a new sprite (arrow), a new code to switch
backdrops, a new code to broadcast a ‘send bat’ message and a speaking code for the characters.

Can you make a new sprite invisible when it is not active? Children follow
further instructions on the Activity Sheet.