1) have shown�� A recent occurrence, present perfect
2) be desensitized- future simple passive, children will be the object to desensitization
3) aggressively - aggressively, adverb needed to modify the verb
4) watching � although an infinitive is common after the verb try , gerund is preferable when you mean you are doing something as an experiment, to see what will happen.
5) are watching � otherwise there wouldn�t be �playing �J))) something is happening at a particular present moment
6) will enable/enables � both are correct, a general action/state in the future / present