Added TRASH CAN

I have been away from my project for a couple of weeks because I needed to focus on closing out the school year. I now have my students working on balloon cars and catapults....and it is a 3-day weekend, so I have a bit of time to get back to this project.

Today I worked on creating a second puzzler question... but this question had a couple aspects that have added a few tools to my tool bag.

First: Most significantly, I have added a TRASH CAN to the "dots" list.... (You can see it in the bottom/right corner) This will be a location where some draggers might have to be placed.... for the students to get the answer correct. In other words: I can now include EXTRA draggers/answers and the students have to decide if they are extra or not.... They have to make the decision to throw away some answers. This makes it harder to just guess there way through the problem.

Second: I have added a new dragger object called "F" which includes a chalk-font subscript word. I can alter the word when each "F" object is created. In this scene you can see Force of Gravity (F of "g")... Force of Ice (F of "ice") and Force of Push (F of "push")...   There will be many times when I can use this object.

Third: I made the clicker-drag engine able to work in STAGES..... Instead of just ONE big set of answers, the students in this scene will FIRST set up the vectors, then progress on to the second set of click-drags where they have to set up the labels on the vectors. Only after the student has gotten BOTH stages correct do they get the entire problem correct. This required a bit of adjustment in the program. (Again, I can use this in future questions)

Time: 7 hours