One thought could be showing the new students the code from last year; what each program looked like and how said level of programming works.
Afterwards, give them a task relating to that level of programming (have them write a program for a standard tank-drive chassis, etc.), check up on each of the students and correct them on what they are doing and how they can make their program better.
Before the meeting is over, gather all of the students and review the code for the program.
Its so the students get hands-on work of intermediate/advanced programming, and they will learn the thought process in the end. Hope this helps!
