I'm wondering how good Esperanto is as a "starter" language for other languages. I know it can help grasp grammatical concepts. I picked it up a while back, but it fell by the wayside. At the time though, it really helped me grasp concepts in English and Spanish.
So how effective is it to learn esperanto to prepare you to learning another language? I think it would help a lot, but I would like to hear what people know.

This article might be interesting for you.

mnlg:This article might be interesting for you.

There's an interesting scheme using the propaedeutic value of Esperanto for primary schools here.

This point is a favourite with E-o apologists, but I am uneasy about emphasizing it. E-o is first and foremost a bridge language. It is not intended either as a substitute for national languages or as a preparation for them, though it may accidentally do so in the case of Romance languages. In the classic experiment, the benefits of doing 1 year of E-o followed by 3 of French versus 4 of French were only seen with the less able pupils.
In short, if people are drawn to learn E-o by the thought that it will help them learn Romance languages, IMHO they have been drawn for the wrong reasons, even if it works! That said, if they then become keen E-ists, well and good.

Miland:This point is a favourite with E-o apologists, but I am uneasy about emphasizing it. E-o is first and foremost a bridge language. It is not intended either a substitute for national languages or as a preparation for them, though it may accidentally do so in the case of Romance languages. In the classic experiment, the benefits of doing 1 year of E-o followed by 3 of French versus 4 of French were only seen with the less able pupils.
In short, if people are drawn to learn E-o by the thought that it will help them learn Romance languages, IMHO they have been drawn for the wrong reasons, even if it works! That said, if they then become keen E-ists, well and good.

It does also mean they'll know about it and be able to speak it to some extent, so if they encounter it somewhere afterwards they're more likely to be interested in it and less likely to dismiss it because of ignorance of what it is. Also, if that initial learning of Esperanto includes interacting with learners in other countries (such as a link between two school classes), they'll be able to see that it works, and what its advantages are compared to using national languages.

Also, the studies on this have found that Esperanto helps with learning languages other than the romance ones, though not as much.

Miland:This point is a favourite with E-o apologists, but I am uneasy about emphasizing it. E-o is first and foremost a bridge language. It is not intended either a substitute for national languages or as a preparation for them, though it may accidentally do so in the case of Romance languages.

It's the reason I learned Esperanto. I made a decision that I wanted to learn a foreign language,but I didn't have any particular choice in mind, I just wanted to develop that skill. I thought about German, because I had a lot of German in college and had a good reading proficiency in it back in the day. I thought about Spanish because of its ubiquity and usefulness in my homeland (america). I considered some more exotic languages too. Then I discovered Esperanto. It tempted me a lot. Ease of learning, Pasporta servo, how cool is that? Spoken by millions...well at least hundreds of thousands all over the world. Great Literature to read. A community of amazing people. Much temptation indeed.

But, I was not yet convinced. Then I read about the studies of people learning Esperanto then other languages. Two groups, one studying Eo for a year than french for three, and a control group studying only french for all four years. The Eo group not only learned 2 languages in the 4 years, they learned french as well as the control group which spent an extra year on it. It's like they leaned Esperanto for free. To me that was the most powerful inducement of all, and it tipped the scale in Eo's favor (for me). By itself, that wouldnt have convinced me. But, it was final push I needed.

Not only have I learned Esperanto, I've learned a huge amount about my native language. I'm convinced that Eo would be an amazing way to teach kids about grammar in school. It's certainly easier to understand Eo grammar than it is to understand English grammar. Then they could learn the grammar of their own language by analogy.

I just started learning Spanish as my third language. And yes, the fact that I know esperanto is a huge help in that endeavor. Personally, I think if we want to extol the virtues of Esperanto, it's better to not leave any of them out. Dr. Zamenhof didn't make conditions about how esperanto should be used, he made it a gift to the world. How we use it, and how we work to make it grow, is up to us.

I'm something of a beginner here, but I believe it is relevent to point out that even the little Esperanto I have learned thus far has helped a TON with my German.
Not only that, but I now have a much greater appreciation for English grammar as well.

steel:...but I now have a much greater appreciation for English grammar as well.

Thanks for making that point steel. Lots of grammatical concepts that bored me to tears in high school became clear when I encountered them again studying other languages.

Gatton:

steel:...but I now have a much greater appreciation for English grammar as well.

Thanks for making that point steel. Lots of grammatical concepts that bored me to tears in high school became clear when I encountered them again studying other languages.

So true. And there's a lot of English grammar that is never taught. In my lit class a bunch of the (native English-speaking) students end up resorting to French to describe the grammar elements.