To Tech or Not to Tech....

I am back in the classroom after a two year stint as a technology resource teacher.  Teaching 8th grade science.  I am a bit torn.  Last year at this time, I had used computers twice in nine days.  After nine days this year, I have not used them once.  Where is the line?  Most computer programs do not allow kids who use them for assignments to make mistakes; real scientists DO make mistakes.  In other words, I do not see programs for science that allow errors.  Real science makes mistakes; measurement errors, calculation errors and so on.  Software does not allow this.  So when do you use tech as a substitute for a good hands-on lab with real-world applications?