They should get equal jail time BUT there should be something in the law that discerns a situation between rape and consensual sex.  I agree with Ana on this! 

Yes, a thirteen year old boy or girl may be too young to understand the baggage and everything that goes along with having sex, but they are old enough to know whether they want to have sex or not. The physical thing and the ability to say yes or no is there.  That's the bottom line.   

They know what they are doing.  Hell, I hadn't even gone through puberty at 10 years old but I knew it would be the best thing ever!  It is pleasureable, it can end up in pregnancy, it is taking a relationship to a different level, it is risking STD, it is fun, it is scary.  They know this.  A 13 year old knows the difference between saying no and saying yes.  "No" means he/she was raped.  "Yes" means he/she wanted to and it was permitted.  This would be easy to add to the law!

No, an adult - teacher or anything else - needs to really weigh the concequences here (especially in today's society) for him/herself and for the other person.  80 years ago, it wouldn't have been as big of a deal.  I knew a teacher, now deceased, that taught 80 years ago.  He had a sexual relationship with one of his students.  She became pregnant.  She had the baby.  The parents were disappointed in this BUT they never considered pursuing legal charges.  The parents accepted this.  The student and the teacher kept in contact.  The teacher never lost his job.  He was not an outcast of society and was never charged under any law.  Things have changed drastically...