Do You know that You can make fully functional vending machine from the standard lego bricks ? No springs, no gears, just bricks. It's not hard but it could be very cool project for Your kids or for You (if You like lego and machines)
Oh, You don't need any special lego. Just take what You have in Your lego chest. It probably would be enough.
Step 1: Chasis/automat Body
Automat looks like a cube. On the picture You have description what is what, but mainly You need to build the frame with two chambers - one for coin and the other one for the candies. In the middle of the chambers there will be a dispencing mechanism.
Step 2: Unlocking Mechanism
Unlocking mechanism has the shape of T-letter (more or less).
From the left-in coin chamber-You have two bricks (marked on th epicture with green color) which allows to lock the movement of the whole mechanism. If You put T-letter part into it it will be blocked by the green brick. When You put the coin on T-letter part, coin will push the locking mechanism down, and You will be able to move the part forward.
When You move it back, the lock mechanism will again be in place which will block further movements forward. It is hard to describe, but it is easy. You can see it on the video.
Step 3: Dispensing Mechanism
When You put the coin, the T-letter part will be unlocked and You will be able to move it forward. If You do it, the candy will drop. When You move the part back again, the candies will be blocked and they won't drop any more.
Step 4: That's All.
The lego vending machine is ready to use. I did not write how to exactly built the device frame, because You should use whatever You have in Your home (as I and my son did).
Thanks for reading!