Hiragana: [ a ] [ ka ] [ sa ] [ ta ] [ na ] [ ha ] [ ma ] [ ya ] [ ra ] [ wa, wo, n ] [ ゐ and ゑ (ancient hiragana in disuse) ]
Katakana: [ a ] [ ka ] [ sa ] [ ta ] [ na ] [ ha ] [ ma ] [ ya ] [ ra ] [ wa, wo, n ] [ ヰ and ヱ (ancient katakana in disuse) ]
Welcome to the first installment of the hiragana lessons. In this lesson you are going to learn how to read and write the Japanese vowels, "あ", "い", "う", "え" and "お".
U - It's the lowercase u from the Latin alphabet. Tilt your head to the left, it's a sideways u.
The Long Vowel Sound 
One can extend the vowel sound of a kana by affixing either a あ、い、or う depending on the vowel. The vowel would be extended for one more mora, or beat. In most cases: あ follows あ; い follows い or え; う follows う or お.
There are rare exceptions where an え vowel is extended by adding え or an お vowel is extended by お. Some examples of this include おねえさん (oneesan or onēsan), おおい, and おおきい (ōkii).
One giveaway to an English-speaking accent in Japanese speech is the use of a diphthong for the elongated "e" sound (Such as the sound in "Eight"). In actuality, "えい" is pronounced correctly by speaking the え sound twice as long as normal.
It is important to make sure you hold the vowel sound long enough because you can be saying "middle-aged lady" （おばさん）(obasan) instead of "grandmother" （おばあさん）(obaasan or obāsan) if you do not stretch it out correctly.