Should i go to summer school, eventhough i passed the regents?

i could'nt get a hold of my counselor. i will be a senior next year. i have 36 credits. its my first time in a american school and i was having a hard time with my US history, i passed 2 marking periods and failed the rest. (my final grade that was written was a 65.haha) BUT i passed the regents with a score of 66. they told me to go to summer school. should i go?