In making flowchart subjects: basic programming and algorithms, I use Raptor applications that you can download from this site.
Why do I use a raptor because facilitate students in making flowchart that can be executed directly, to check the flow of the program.
Raptor display examples:
Thanks to Dr Martin Carlisle, creator of Raptor
RAPTOR is freely distributed as a service to the CS education community. RAPTOR was originally developed by and for the US Air Force Academy, Department of Computer Science, but its use has spread and RAPTOR is now used for CS education in over 28 countries on at least 4 continents.