Second, I would tell myself that it is important, when making bar charts, to get the labeling at the top right. That way anyone trying to read your bar chard can understand it. Ki+Ug,i+Us,i+W+Kf+Ug,f+Us,f+(delta)int. This all means initial kinetic energy+ initial gravitational potential energy+initial elastic potential energy+ work+ final kinetic+ final gravitational potential energy+final elastic potential energy+ the change in internal energy. Thirdly, I would tell my past self that when you add up the initial energy and the work it should equal final energy. If the final state has more or less total energy than the initial state than positive or negative work must have been done by an outside force, so you should draw a bar in the work column. The number sentence should always be equal.
Fourthly, i would explain energy transfers to my past self. Energy transfers is when you have one type of energy in the before section of your energy- bar chart and another type (but the same amount) of energy in the after section of the bar chart. For example, if the initial state of a bar chart is a marble is high up in a marble ramp [friction free] , it might have 3j of gravitational potential energy, and the final state is it moving (it is almost at the bottom of the ramp) it may have 3j of kinetic energy. no work was done, the energy was just transfered. The night that we practiced doing bar charts with the money examples is a good thing to show my past self. Those helped me understand the whole work section of the work-energy bar charts.
this link explains work-energy bar charts:
http://www.physicsclassroom.com/CLASS/energy/u5l2c.cfm
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