This is to hard
I am 13 and just started 8th grade and want to learn Spanish! But this comes to far of just beginning to think we can remember everything even if we dont know it!
Keep going. If you do a few lessons every day, keep the tree gold, and make slow but steady progress through the course, you'll be amazed how much you know at the end of a month. ...and then think how good you'll be after a year.
No need to despair! Learning a new language is a little difficult at times, but it's still possible.
You don't have to move on to the next lesson if you don't feel like you've fully learned the last one yet - you can always do it again. There is nothing wrong with learning things slowly and thoroughly!
Learning a second language is hard, a lot harder than popular culture makes it out to be. Unless you're immersed in the culture, it takes many years. But it helps to be young, and you're still young enough that you'll have an advantage. For you, it will probably take about two years of daily study. For someone my age, it could easily be five. So keep going - by starting now, you'll be saving yourself three years of study! It's a bargain.
When you are in lessons and the Words and sentences are coming up you can hover over them and see what they mean.
Keep going. Language learning is a funny old thing, we learn without really knowing we are learning. I believe a lot of our language learning is subconscious. Quite often I'll recall a word whilst doing an exercise without actually even thinking on that word. Our minds are incredible things and you will get better - Spanish is a lot of fun to learn too!
For me learning Spanish and German on DL, I found some parts of the language too difficult on DL and I needed extra help. So far it's been easy to find other resources on the web that practice these parts. For example genders in German or verb conjugations or Spanish determiners.
You'll find many good additional resources on this page: http://duolingo.wikia.com/wiki/Spanish
Ask help to find additional resources if you get stuck!