Ipod is the trade name for mp3 player by Apple. it basically plays music (video with higher storage capacity and new generation), records your voice and play radio (with some models). There are many companies producing mp3 players. The price ranges from $30 to more than $300 depending the brandname. Ipod by Apple is always expensive. Mp3 players are sold in any stores that carry electronic items such as walmart, circus city, best buy, office depot... You can also find it online. To get some ideas about brandnames of mp3 players and prices you can type the key word mp3 player in www.amazon.com or www.buy.com. They should list all mp3 players that they carry. The common capacity for a mp3 player now is about 2G. The more capacity, the more songs your kids can store in it (depending what type of files). If you budget for less than $50 each mp3 player you can go with 2G one. It's good enough for kids up to 15 yrs old. Right now Buy.com has 2G Sandisk mp3 players for sale at $26.99 with free shipping.
http://www.buy.com/prod/sandisk-sansa-m2…
Do some some searches to compare price if you have more time. If you don't this $26.99 is pretty a good deal. Also when you buy (if you do) choose mp3 players that have screen because it allows you to see what song is playing and you can skip or choose other. More information should be under technical info.
I hope it helps
the ipod shuffle cost about $75 but the other ones (nano, video, touch) they cost over $100.
the ipod shuffle (cheapest one) is a digital audio player designed and marketed by Apple Inc. Apple branded it as the "world's smallest MP3 player". This size includes the new built-in belt clip; the actual unit itself is thinner, with the entire device weighing only 15.5 g (0.55 ounces).