TALLAHASSEE, Fla. -- The National Head Start Association is describing a Houston couple as "angel investors" after they donated $10 million to help reopen classes for thousands of children affected by the federal government shutdown.

Laura and John Arnold of Houston offered the cash so Head Start programs could open their doors through the end of October.

In Tallahassee, teachers hung a cheerful, hand-drawn sign outside a Head Start facility saying, "Welcome Back Parents and Children."

The government shutdown closed Head Start programs in six states including Florida. Nearly 400 children and about 100 teachers were locked out of their classrooms for one week in north Florida.

Now the children are back in their classes, happily singing songs and learning again. They're also receiving meals, dental care and medical services.

Head Start Director Laurie Gan Leiner says it was a tough week for students and their parents. Some had to miss work, and paychecks, to take care of their children.

"It was very difficult for them. It was also very difficult for our staff. We were worried that parents might have to pull their children out, or staff might have to find other jobs. Luckily everybody has returned. Some parents had to send their children out of town to other relatives so they could be cared for, so they could continue to work."

Leiner said parents, children and staffers are ecstatic that classes have resumed.

But the emergency $10 million grant from Laura and John Arnold will only keep Head Start programs open through the end of October, so teachers and parents still feel some anxiety over the possibility of another shutdown.

"If Congress doesn't start speaking to each other better then we don't know what will happen November 1st. If this continues past November 1st then there will be another 150 programs that will be impacted because that's when their fiscal year should start."

It's estimated more than 85,000 children in 41 states would be affected if the shutdown continues into November.

Leiner said explaining to the young pre-school students why their classes are shutting down has been a challenge.

"One of the children said, 'Why were we closed?' So it's interesting to see that even the children are aware that something is going on and it's kind of hard to explain to them. They are all so happy to be back at school."

The Arnolds' payment of $10 million to Head Start is an interest-free loan that will be repaid if Congress passes a budget that's retroactive to October 1.

However if it's not retroactive, then Head Start will not have to repay the money.