tonight on "world news," on a roll. it's a winning week. new job numbers are up. gas going down. double barrel relief for millions of americans. on alert al qaeda's playbook to attack america is uncovered in a compound, as president obama thanks the troops that took osama down. mississippi rising. with the highs water since the great depression. thousands forced to flee. sneezing season. why this might be the most miserable spring yet for allergies, and what you can do to stop the suffering. and, priceless. you can't measure a mother's love. but this mother's day weekend, someone has tried.

good evening. and what a week this has been. it began with word that bin laden is gone and it's ending with encouragement for everyone who drives a car or needs a job. today, we got the numbers so many americans have been waiting for. first, a strong new jobs report. 244,000 more people were hired last month, with the best private sector growth in five years. then, the dizzying drop in oil prices. they've plunged by almost $17 a barrel this week, and that means lower prices are already showing up at the pump. jim avila found one of them and he starts us off tonight. good evening, jim. >> reporter: good evening, george. those big fours you've been seeing may be soon back in storage. crude oil prices are down for the second day in a row, and analysts say that could mean a drop in gas prices up to 20 cents a gallon very soon. and gas buddy.com says it's already begun, with prices

dropping nearly a penny since midnight. a gas war. yes, you heard right. prices are already going down in some parts of the country. this is milton, florida, on the panhandle, where regular unleaded dropped from the $3.80's to $3.55 in one day. >> what was the price? >> cheaper than down the street. >> reporter: oil prices fell for the second day in a row. look at this chart. a steady rise from $75 in may of last year to more than $110 last week. and now boom, the second biggest drop in history. down to $97 a barrel. if pump prices continue to settle, seattle's cheryl sanders might actually drive her new car to the mall and spend some more. she was out of work for seven months, but is now re-employed on a personal economic recovery and feeling better about buying. >> i'm not worrying so much about the little things. if we want to go out to dinner, we do it. and it's nice to not have to worry about every penny that's

going out. >> reporter: in fact, today, americans were delivered a trim p whammy of encouraging news. private employers went on a april hiring spree. 260,000 new jobs. the stronge esest gain if five years. gas prices, instead of heading to $5, are forecast to be well below $4 by memorial day. and the essentials? one spiking food prices are now in line with inflation. while clothing prices are down and dropping. >> we are finally hearing good news again and we've been hearing it consistently since the beginning of the year. >> reporter: here's one in chicago. a family-owned company that actually makes things. a manufacturer. and hiring. >> we hired two people at the beginning of this year and we are looking for who positions in our factory that we are looking to fill immediately. >> reporter: and here's a fact to savor over the weekend. at the high of the recession, americans were losing 750,000

jobs a month. this year, they're gaining 192,000 jobs a month. gaining. but even with all that, economists remind us that things that were so good during the recession, we still have a long way to go. george? >> we do, but that is good news tonight. jim, thank you. we're going to turn now to the latest on the mission against bin laden al qaeda confirmed today that he was killed and vowed to retaliate, saying americans' happiness will turn to sadness. but we are learning more about the mother lode of intelligence taken from bin laden's compound. pierre thomas joins us tonight. and pierre, these bin laden times could be the most valuable intelligence breaks ever. >> reporter: indeed, george. as investigators review a mountain of intelligence from osama bin laden's compound, sources say it's clear, bin laden thought of himself as a head coach, overseeing strategy, blessing and approving plots. the materials, including

notebooks taken from the bin laden compound, is both a strategic playbook and a greatest hits album of al qaeda aspirations. while no imminent plots have been incovered, it is clear that bin laden was constantly consulted on ways to attack the u.s. >> they were bringing bin laden materials that may have had p t plots on them. we know in the past he's approved specific attacks and he sent attacks back for further work and further analysis. >> reporter: the materials include numerous hallmark al qaeda plots, including attacks on water supply and transportati transportation. in the past, al qaeda planned for attacks on water supplies have included on poisoning water. the documents say there was clear intent on new york, chicago, los angeles and washington, d.c. and contrary to what many analysts thought, a strategy to attack americans on holidays and

anniversaries. bin laden also apparently sought to recruit minorities to conduct attacks the goal, to not only kill and maim, but to create class warfare and set in motion a destruction of american society. >> by using the tool of minorities as terrorists, i think he wants to create unrest. >> reporter: the documents seized include names, addresses and phone numbers that could prove to be safehouses and suspects. now, george, it's a race against time to track these people down. >> we're going to learn a lot more tomorrow. okay, pierre, thank you. also today, president obama delivered his personal thanks to everyone who carried out the bin laden mission. including those super secret navy s.e.a.l.s who stormed the compound. it all happened at ft. campbell, kentucky. and jake tapper is there. you've learned a lot more about what happened during that meeting. >> reporter: away from cameras, president obama did not just thank the navy s.e.a.l.s, green berets and night stalker helicopter pilots that killed

bill laden. they offered the president a detailed briefing on what went on, using a laser pointer, photographs, maps and even a small scale model of the compound. president obama told the 2,000 troops of the 101st airborne about his private meeting with their brothers in arms. >> chance for me to say on behalf of all americans and people around the world, job well done. >> reporter: presenting the special forces with the highest honor a presidential unit citation, he told them they're the finest small fighting force in the history of the world, and one reason he ordered the operation was because despite risks and uncertainty, i had 100% confidence in you. >> they practiced tirelessly for this mission. and when i gave the order, they were ready. >> reporter: ft. campbell is home to 36,000 active duty troops, 949 of whom returned from afghanistan in the last week. the president praised all of them for their sacrifice and reminded them of why the u.s. is

in afghanistan, relaying the letter he received earlier this week from payton wall, who was 4 on 9/11 when her father, a cantor fitzgerald executive, called from the world trade senter to say good-bye. >> payton remembers watching her mom sobbing as she spoke to her husband and then passed the phone to payton. and in words that were hard to hear but what she's never forgotten, she said, he said to her, "i love you, payton, and i will always be watching over you." >> reporter: the white house released this behind the scenes video that shows the moments when the president and his team learned the mission was a success. >> good job. it was him this was him. >> reporter: the vice president, taking to the phones to inform congressional leaders. >> the reason i'm calling is to tell you we killed -- we killed him. >> reporter: the president thanking his cabinet and advisers for a job well done. >> fwad job, national security team.

thank you leon. yeah. proud of you. you guys did a great job. >> they did. >> reporter: and george, one of the special forces in that closed door meeting reminded the president that a dog was part of the assault team. a dog that is here on base and suggested to the president, jokingly, that if he wanted to meet the dog, i recommend you bring treats. george? >> stay away from those tie tame yum teeth. jake, thank you. tonight, there will be a special edition of "20/20." revealing new details about those bold navy s.e.a.l.s and the specially trained dog jake just talked about, who was by their side. one more note on the war on terror. news late today about another most wanted terrorist, this time in yemen. officials tonight confirm that a u.s. drone strike there tried to kill anwar al awlaki, the radical american-born cleric. the officials say the missile just missed. and the mississippi river is on the rise tonight, and many of the millions who live on its

banks are facing a decision. should they stay or flee what could be record flooding? steve osunsami is in millington, tennessee, where evacuations have begun. and steve, the worst is yet to come. >> reporter: good evening, george. behind me is big creek and it's getting bigger and bigger by the minute. swallowing homes. there are a few stop signs behind me that you can barely see. there's still the larger problem. the mississippi. today, it was just too much for rita watson. she could barely walk out of her memphis home. >> where do you start? >> reporter: everything she owned in the world was either soaking in her house or sitting painfully on the driveway. >> rest of it is no good. it's gone. we woke up and the water was halfway to the fence. the next morning, it was over the gas meter. and this is where it's at now. never seen anything like it before. never. >> reporter: it still could be so much worse. already, the mississippi is higher than it was during the flood that ruined memphis in

1927. today, there are levees and flood gates, most of them are holding, but most of them are leaking, too. is this a loss? >> i would think it would be. completely. >> reporter: the police are now going door to door, urging families to leave. >> well, we have to get out of here pretty soon. >> reporter: because the big river is forcing the little rivers to flood. >> it's a hard situation to deal with, but sometimes you just got to buck up and do it. >> reporter: they're calling it a disaster in slow motion. moving down the mississippi. expected to crest at memphis on wednesday. natchez, mississippi, may 22nd. baton rouge, may 23rd. new orleans, the next day. >> you have a crest that could last seven to ten days but elevated water levels last for weeks after that. >> reporter: the water has already closed highways. on interstate 40 between little rock and memphis, the detour is two hours long. a sewage plant in memphis is holding on, still operational, but surrounded by rising water.

the mississippi has flooded this regional airport. the water is so high, this is a plane poking through. one neighbor we talked with said he believes this is god's plan and that he gives everyone here plenty of time to get out of the way. george? >> and they are going to move tonight. okay, thanks steve. still ahead on "world news," a stunning increase in allergies. what's behind it, and how you can find relief. if you add up all the jobs mom performs, what should she get paid? the numbers tonight. and the 4-year-old boy who saw the towers fall on 9/11. how a firefighter's words saw the towers fall on 9/11. how a firefighter's words changed his life. business is! it must be if you're doing all that overnight shipping. that must cost a fortune. it sure does. well, if it doesn't have to get there overnight, you can save a lot with priority mail flat rate envelopes. one flat rate to any state, just $4.95. that's cool and all... but it ain't my money. i seriously do not care... so, you don't care what anyone says, you want to save this company money!

that's exactly what i was saying. hmmm... priority mail flat rate envelopes, just $4.95 only from the postal service. a simpler way to ship. so i've got to take care of my heart. for me cheerios is a good place to start. [ male announcer ] to keep doing what you love, take care of your heart with cheerios. the whole grain oats can help lower cholesterol. love your heart so you can do what you love. ...but my symptoms kept coming back... ...kept coming back. then i found out advair helps prevent symptoms from happening in the first place. advair is for asthma that's not well controlled on a long-term asthma medicine, such as an inhaled corticosteroid. advair will not replace a rescue inhaler for sudden symptoms. advair contains salmeterol which increases the risk of death from asthma problems and may increase the risk of hospitalization in children and adolescents. advair is not for people whose asthma is well controlled with a long-term asthma control medicine like an inhaled corticosteroid. once your asthma is well controlled your doctor will decide if you can stop advair

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so it's easier than ever to keep your house smelling just the way you want it. purina tidy cats. keep your home smelling like home. check out that grass behind me. it's signaling spring is in full bloom. but for many of us, it's a mixed blessing. for the 35 million americans who suffer from hay fever, this might be the worst season ever. so, we asked linsey davis to tackle two questions. what's behind it, and how can you find relief? >> reporter: if you're experiencing itchy eyes and sneezing and wheezing earlier than usual, you're not alone. >> a little bit before spring happened it started getting bad for me. >> i find mooirs more frequently looking, where's the next tissue. >> reporter: last year's allergy season was deemed the worst on record. but thanks to heavy winter snopes and early spring rains, 2011 is poised to be even worse. pollen levels are already

reaching record highs. researchers monitor ten sites across the u.s. and canada, between 1995 and 2009. they measured daily temperatures and corresponding pollen count. their findings are nothing to sneeze at. they say higher temperatures are causing people to sneeze, snort and sniff earlier and for several weeks longer. in papillion, nebraska, pollen season grew by 11 days. lacrosse, wisconsin, 13 days. and residents of minneapolis, minnesota, had 16 additional days of suffering. scientists may have found a connection between the farn tithe scale and the gesundheit scale. they say as the earth's temperature rises, so does the messry index of allergy sufferers. the increased carbon dioxide doesn't just raise global temperatures. >> it speeds up plant growth so that plants are capable of producing more pollen. >> reporter: and that means people who never suffered before

are now. >> there are a lot of patients who are calling us, describing severe symptoms and some people are having symptoms for the first time. >> reporter: one huge help for allergy sufferers, turn on the ac. air conditioning is known to be able to cut down the amount of pollen we breathe in by at least 90%. and for those of you who suffer from asthma, be aware that spring blooms and even thunderstorms are known to keep people grabbing for tissues and eye drops. george? >> linsey, thank you. and when we come back, valuing moms. trying to put a price on all the work a mother does. [ robin ] my name is robin.

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for all of you still out shopping for mother's day, there's a new measure tonight of how much we owe our moms. it's a lot more than flowers, but a lot less than many of you might think. here's john berman with the price tag that's sure to set off a mother's day debate. >> reporter: june cleaver, carol brady. for everything she does, what do you think mom is worth? how much money do you think your mom deserves? $5? >> reporter: for a more accurate measurement, the website insure.com used government wage figures and identified 14 separate jobs mothers do. 40 hours of child care a week at just under 10 bucks an hour would run more than $20,000 a year. nine hours a week driving at $13

an hour for a taxi, more than six grand. cooking almost 7,000, cleaning almost 5,000. then, how about party planning? 1,500. and someone has to find the kids a replacement private detective could cost $800. add it all up, and insure.com says mom is worth $61,436. now, that's good money, but it doesn't take into account the 77% of mothers who have jobs outside the house. and it also misses the boat on mom because -- >> she's had more of an impact on my life than anyone i can imagine. >> you can't put a dollar figure on what my mother's worth. >> my mom's like, my best friend. >> reporter: no, the math doesn't take into account caring and it doesn't take into account love. >> mom, i love you so much. >> reporter: until you can put a dollar figure on a hug, mom is, and will remain, priceless. john berman, abc news, new york. >> amen to that. and still ahead, how a fi

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finally tonight, all of us have been reminded all week of that september day nearly ten years ago, when america was attacked. and for one boy, they are his first and most powerful memories. his entire life has been shaped by what he saw and heard on 9/11. here's david muir with our "person of the week." >> reporter: the morning of september 11th. kinder fwarten class had just begun. second day of school? >> it was. >> reporter: barely into the school day, a 4-year-old boy named brook would soon be in the arms of his mother, racing from the school. the twin towers had been hit. his single mother was following a familiar instinct, heading to the fire house where she had taken brook so many times before, looking for male role models for her son. brook grew up there. and as the firefighters left for those towers, a heavy request for that little kindergartner. >> tell my wife i love her. tell my kid this. and it was all just very hard,

because i couldn't remember who to tell what to afterwards. >> reporter: and there was one message that stood out most of all. a firefighter says to you -- >> grow up and be a good man. take care of your mother and be a good man. >> reporter: never forgotten that. powerful words. >> yeah. yeah. they're good guys. i mean, at the very end, they were still looking out for everybody else, but also my very boy. >> reporter: then, the towers collapsed, and brook was being carried by his mother again. she told him to bury his face in her shirt, to protect himself from the dust and debris. but his kur you eyes were peering over his mother's shoulder. >> my head was facing the towers as they were falling. >> reporter: and there was something else. >> i remember something to so vividly. it looked like a stick figure,

just from them being up tremendously high. but it was a businessman with his briefcase and just falling towards the ground. >> reporter: impossible to comprehend for anyone, let alone at 4 years old. but that fire house alone, 11 men did not come back. you've struggled with what you saw that day? >> i still do. >> reporter: convinced he wasn't alone, that other children saw what he did at just 4, brook began putting together a documentary, interviewing other children who had grown up. >> this was my first full day of kindergarten. this was my second. >> reporter: this is a tribute to the other students and the teachers. >> and their heroism on that day. >> reporter: the teachers who held onto their students thanes. brook just finished his film. it premiered in new york last saturday. one night before the world learned osama bin laden was dead. all these years later, he told me of a simple wish, women, two of them, to be exact. you want to grow up to be a filmmaker. >> a filmmaker and a fireman.

>> reporter: you've got the filmmaker part down. have you been doing your pullups? >> i have. >> reporter: training, and even today is guided by that firefighter who told him when he was just 4. >> and so we choose brook peters. in the last week, he's gotten standing ovations, but he says the biggest honor will come in three years, when he becomes a fireman. thanks for watching. you a kuls watch the latest on abcnews.com. and don't forget, that special edition of "20/20" tonight. david muir will be here all weekend. i'll see you monday on "good morning america." for diane sawyer and all of us here at abc news, have a good night and a happy mother's day.

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