Although - linking word - expresses the idea of contrast.
e.g. - Although Amit has a car, he doesn't often drive it.
The clause with although can come at the end.
e.g. - Although the cafe was crowded, we found a table. OR We found a table, although the cafe was crowded.
Though - is informal. It means the same as although.
e.g. - Though / Although I liked the sweater, I decided not to buy it.
We can use though at the end of a sentence.
e.g. - I liked the sweater. I decided not to buy it, though.
Even though - is stronger, more emphatic than although.
1). Ram looked quite fresh, even though he'd been playing cricket.
2). Even though you dislike Sanya, you should try to be nice to her.
Note - We can use in spite of the fact (that) in the same way as although.
I'm no better, although I've taken the pills.
I'm no better in spite of the fact that I've taken pills.
Quick Tip only for GMAT -- Applicable most of the times but not always ...
Even though -- when the condition given is negative but the outcome/result is positive
e.g. -- Even though Ram hadn't studied, he passed the exam.
Although -- when the condition given is positive but the outcome/result is negative
e.g. -- Although Ram had studied very hard, he did not score well.
Mr. EGG explains the usage in simple way via cartoon on the link below:
Although vs. Even though