For clarity, I will use FULL_STOP instead of '.'. Also, I will not correct other grammatical mistakes, such as missing articles (e.g. it should be the student can choose the next step). I will try to limit myself to correcting the punctuation (except that I have used empathizing, which is a perfectly fine word; in contrast, emphasizing with the feelings of another, as you have it now, is not acceptable.)
I will show one way to place the periods so that you have complete sentences, which is at least consistent with The Chicago Manual of Style. Of course, you should actually use whatever style manual suits the needs of your client.
I know you said you don't want to make 'major' changes to the text. Nevertheless, unless these are supposed to be mere sketches or bullet-pouints in a presentation (in which case, do you really want or need the periods?), I urge you to do a bit of rewriting on these sentences. If they are supposed to be part of a self-contained, in-principle-publishable academic text, they need to be rewritten!
In the end, the periods just go to the end. Only in the second sentence is another intervention needed, namely, replacing a period in the middle by a colon.
Student will demonstrate empathizing with the feelings of another by remembering a similar past experience and sharing it for comfort (e.g., “Last year I was unfairly accused of cheating by a teacher so I know how you must feel now”)FULL_STOP
Student will make a reliable decision in play (e.g., when given choices of what to do next with the doll, student can choose the next step: “Does she want to go swimming or eat broccoli?”)FULL_STOP
(Note that there is now a colon rather than a period after next step.)
Student will express more complex emotions using visual supports, communication and affect (e.g., sick, tired, anxiety, confusion, etc.)FULL_STOP
Note that I have placed a period after etc. I did this because e.g. had periods; either both of those should have periods, or neither. (Thanks to Edwin Ashworth for pointing this out.)