This version employs the metaphor of locked/unlocked numbers for representing specific vs general numbers. That is, unlocking turns the number essentially to a general number. It lets you change its value but it also lets the system change its value in the “General World“. The animation then in the parallel world is the way to evaluate your construction.
Note: This version also includes a prototype implemention of the help request mechanism through drop-down menus that we envisage students will use to ask help from the system. At the moment it is used for wizard-of-Oz studies (so don’t expect any help, the wizard is away ;-))