$150 dollar budget - 6 kids to buy for, 2 are my step kids... what do i do?

i have been living off meager unemployment funds of $129 a week for several months, and its just barely scraping the bills.. in any case, i have to buy presents for 6 kids - my 17 year old nephew, niece whose 13, niece whose 11, niece whose 5, and stepdaughters who are 5 and 7... i know i will have to spend a little more on my step kids then everyone else, but in all reality, i have no idea what to get my nieces and nephews that they will appreciate... they are the kids who have everything, so its very hard.. and gift certificates are no good because i really only have a $15, maybe a scant more, budget for them.... i need help... cant bake cookies either because my other sister does that on top of giving gifts... what do i do?