I can't do a real pull-up or chin-up. I had been standing on my aerobic step, and jumping up and getting up that way...but it didn't seem to be really using my muscles.
So, I put a chair under my bar, and in front of my step. I put one leg on my chair and one leg on the step, and pull my body up until my back leg is off the floor and I am up to the bar.
Will this help me get stronger? Even if I keep that one leg on the chair? I still feel as though I am using my muscles to pull my upper body up off the ground, and only a fraction of the weight would be on that leg. Then, when my body is used to lifting my upper body, I can find ways to add challenge and gradually rely less on that front leg?

I don't know the logic behind it, but I do it too. I will alternate legs between sets, try to decrease the amount of assistance I'm getting from the leg. I've used different heights to step from, positioned my feet different ways. I don't have a pullup band, so figure this is kinda sorta similar. I do feel the pull on my upper body.

I sometimes do kipping pullups, which are easier for me than regular ones. For some reason my search isn't working on my computer so can't find the video I'm looking for, but you can google it.

Thanks for replying.
I have actually started alternating legs too! haha, great minds think alike? I was thinking that we probably all have a dominant leg, and if I am using that dominant leg in front, it will be easier. If I put my weak leg on the chair, and dominant leg behind, it should be harder.
I do have a band, but I was youtubing videos and the one guy says that the bands are dangerous, so you need to be extremely cautious using them! So, I figured this might be safer. That, plus my bar is in the basement and the floor is concrete...I don't want to risk a fall.

We use bands at our gym. Nothing dangerous about them if used correctly, and as long as the band isn't so old that it's cracking/breaking in two. Just put ONE foot into the band, and hold onto the bar, put a box or chair in place you can step down on if you need to rest and/or the band is too strong to let you drop to the floor with a foot still in it. The band will get you there quicker than anything else, but jumping pull-ups are good, also, especially if you combine them in a workout with something that taxes the legs, like do 10 squats, 5 pull-ups...a couple rounds of that, and you'll still be able to jump to get some momentum, but will definitely be using your upper body to finish the pull-up. The self assist on the chair is fine, too, but harder to keep the assistance consistent...the band is a little better because the assistance is always constant, even when your upper body is fatigued, so you'll get more of a training effect with the band, where with leg assist, it's near impossible not to just put more leg into it, which sort of nullifies the point of the exercise...again, pre=fatiguing the legs with some squats, a sprint like 200 meters, rowing, or similar, will help force you to use your upper body as much as possible. I'd do them all, bands, jumping pull-ups, kipping with the band, switch your grip around..every once in a while try a strict chin-up or kipping swing pull-up without the band, to see how you're progressing. You'll get there!

I can't use bands...I am using monkey bars as my pull-up bar. There would be nowhere to fasten the bands to the bar. And as I said, I was doing jumping pull-ups but not getting anywhere...

The bars we use at our gym are basically one long monkeybar I plan to try to replicate it at home but haven't as of yet.

If you search for 'assisted pullup bands' on google/youtube, you should find various videos.

Here are a couple showing you how you could do it:
http://www.youtube.com/watch?v=fw3FnkqViKo
http://www.youtube.com/watch?v=TindOf7zyXM&NR=1

Thanks, I tried the bands like that, but I don't think that the bands I own will hold my weight...

I ended up buying some like my CF gym has which are strong and meant for assisted pullups.

http://www.ironwoodyfitness.com/fitness-bands.php

Thanks, but I use my monkey bars from when I was a kid for a reason...I don't have the money to buy a real pull-up bar and expensive things like this. My bands came from Walmart for $15
However, I just graduated from college and am looking for a job (*crosses fingers*) I will keep these in mind and they will be on my wish list with all of my fitness stuff I will buy when I get "rich"

I've built my home gym piece by piece So I think as you find yourself able, you can buy things here and there to build it up. I did see a youtube of a guy using regular old bands like you'd find at Walmart but yeah I'm not so sure about that.

Sounds like my gym!! I try to get one thing a month that is new to keep things "fresh". But I find most of my stuff from yard sales or thrift shops, like 1-3$ workout dvds. I even found a stationary bike for $10!
I was buying dumbbells from Walmart, up to 10...but they got expensive!! Kettlebells too..and that is why I got those bands.
Now, for strength I am just focusing on body weight stuff, like push-ups, pull-ups, and squats...

I found this video really useful, and shows you techniques that don't need a band, especially the first one (lower yourself down instead of pull yourself up).

You'll need to write out the URL as you haven't made enough posts yet to add a link.

Oops. That was annoying. Ok, the video is on youtube and after the slash you type: watch?v=iV1D5OZ2SpM

I think negatives are going to be your best bet, that way you wont have any "assist" Jump up, all the way to the top of the position, and lower yourself down as slowly as you possibly can.

Also, just as an FYI, generally speaking for women, pullups/chinups are really really difficult untill you get below a really low Body fat level.... I hate making generalized statements like that, but untill you get down to about 18-19% BF, yo umight not be able to do them at all....