Hi;

I am trying to create a custom raspberry Pi OS image for teaching and need Scratch on it. Raspbian Jessie Lite does not come with Scratch installed so I installed it by entering ‘sudo apt-get install scratch’.

I needed the version of scratch that includes access to the Raspberry Pi GPIO pins for controlling real world devices such as LED's and Motors.
According to the guide on the Raspberry Pi Web Site to start using scratch with the GPIO you need to turn on the GPIO server which can be done by using the relevant option in the Scratch Edit menu. The version of scratch that I have installed does not appear to have this in the edit menu but does include an option for switching on and off Motor control blocks?

Can anyone help?

If you instead did
sudo apt-get install nuscratch
you'd get the actual latest version of Scratch intended for thePi, with GPIO support and all those useful little speed improvements that make it ~20 times faster.