There are multiple “even though” in Japanese, each with slightly different nuances.
- が, けど, けども, けれど and けれども are the most commonly used and all interchangeable, although けど and けども are colloquial. They all follows 終止形 of verbs, aux verbs, adjectives. As you may have already guessed, けど, けども and けれど are all abbreviations of けれども
- ても (でも) usually expresses “even though I’ve tried, I cannot get the desired result”
- のに is used when the result is undesirable
- ながら and 拘らず are “despite the fact that”, especially there is a clear contradiction between “A despite B”
- くせに is used to express the speaker’s frustration toward the person in question that he/she is not doing what he/she would or should do
- ものの is often “even though you did something with a specific intention, the end result was not quite the same”
- つつ, つつも is usually “even though you know it is not good, you don’t/can’t stop”
- 割に is used when the result is better than, or not as bad as, originally expected