IHMC CmapTools http://cmap.ihmc.us/ for concept map tool. that is the one i was using too. ;D it is great for Explain, i used it for revision.

using the 5e or 7e instructional model [img]http://www.coe.ilstu.edu/scienceed/lorsbach/lcpic.jpg[/img] i would argue that the "Explore" part is critically under develop in most physics lessons.
my experience as a teacher and learner indicate real life experiments and perhaps simulations can support the exploring.

concept map is more an "Explain" tool. after the students have "Explore" and experience the physics, then we can get them to Explain.

i realize people sometimes under estimate the critical role of "explore" or "learning by doing", and start the "Explain" stage of learning without enough emphasis on "explore".
how could the students make sense of the concept map without actually doing the physics (science) ? how would they bootstrap the learning on? on abstraction and idealization of ideas in semiotic representation such as dialogue, text and diagrams?

We learn because we interact with the world (real or virtual lab), after that, i will be more comfortable using concept maps during the Explain stage.

i am glad i am making "better" simulations for the world,  and making the world a little "better" for learning physics.
Thanks for listening to my grumbling  ;D