<p>I’m sorry, I probably replied a little bit to fast. I overlooked some things. 
I saw the activities list, but you don’t have to do those. You can also just study or do other things. 
There is indeed only one engineering course [Tissue</a> Engineering for Clinical Applications | Harvard Summer School](<a href=“http://www.summer.harvard.edu/courses/32841]Tissue”>DCE Course Search)</p>