Chaitra Maas is the 1st month of Hindu Lunar calendar year. The following Vrat and festivals fall in this month.

Chaitra Krishn Ashtamee - Sheetalaa Ashtamee
This Ashtamee is celebrated as Sheetalaa Ashtamee. Sheetalaa Maataa is worshipped on this day with the belief that she will save the people from small pox and chicken pox and other deadly epidemics. For this the food is prepared the previous day and is eaten cool on this day. In North India after this day, people normally do not eat the previous day food any more.

Chaitra Shukla Pratipadaa
This day Brahmaa Jee created this world, so the first Sat Yug starts this day. That is why this day is called Yugaadi (Yug + Aadi = beginning of the Yug) day. This day is celebrated in southern India also with the name Ugaadi.

Chaitra Shukla Pratipadaa - Navamee - Nava Raatri or Nava Durgaa
This is the first Nava Raatri in which nine forms of Devee are worshipped for nine days. the other Nava Raatri comes in Aashwin month, just before Dashaharaa. In this Nava Raatri also, people keep fast for nine days. The 8th day they feed Kanjak and Kanjikaa (boys and girls below 9 years of age), give them Daan according to their economic situation, clothes etc along with some Dakshinaa (money). Pooree, Halavaa, vegetables are prepared for the Naivedya of Devee and for invited children.

Chaitra Shukla Navamee - Raam Navamee
Raam was born on Raam Navamee day. This day is not celebrated with the same vigor as Krishn Janmaashtamee is celebrated, still it is celebrated in a modest way.