Case
Over protective parents

When the first day of school rolls around, many parents are eager to have their children start school. However, there are a few parents are not willing to let their children go. This can be a fine thread to walk. You must handle the situation very lightly. A student in my 3rd grade class was in this exact situation. His parents were constantly calling in asking how he was doing and how his grades were? At what point do you just say "wait for the report cards."

Solution #1
I would inform parents that as a teacher I monitor students' grades and progress daily. I would then tell them I would be happy to send home a note or make a phone call to them at the end of the week if they would like. Also, I would be sure to inform them on other days of the week if there was a need to based on a sudden drop in performance.

This is a good suggestion, keep the parent happy by sending a note home at the end of the week.

This is the exact solution I would have suggested. Student's usually have planners and leaving little notes in them every week could help the parents while also saving you from the phone calls.

Compromise is important with dealing with parents.

Solution #2
I would make it a habit to send home test grades on Fridays, this could be a simple Friday Folder concept. Have the parents review the grades and initial each one. This will not work for some parents but for the ones that are very involved, they will like knowing where their child is on a weekly basis. You could have that particular parent be the helper on Friday's to put this folder together for you. You will be grading the papers anyway so it would hopefully be an easy step to stick them in the folder. I would be sure to write down the grades prior to them going home in case some tests do not make it back to school.
Solution #3
IN this situation I would let the parents know that if there is a problem with their student I will let them know. Otherwise they will get a weekly update and regular progress reports. I am always very happy when parents want to be involved because it makes a huge difference with the students, but it is important not to let it get out of hand.
Solution #4
Maybe you can keep a record so that they can check them online whenever they want. A polite letter letting them know how many students you have might be necessary. Some parents just don't realize their unnecessary behavior unless someone explains it to them. At least they're involved and they care. See if they would like to volunteer in the classroom or do put together things at home (if you don't want them in the classroom).

Having an online record is a great suggestion.

Solution #5
If something like this happens, then work out a plan to send home academic notes during the week. The parents must realize that you have 20 other students that require your attention.
Solution #6
It is normal for parents to be concerned, but that is a bit excessive. That can become a huge disruption to your day. I'd suggest implementing some other form of communication. For example, let them know you will call them if there is a problem. I would personally set it up so they receive a note in a planner home daily regarding behavior and any major problems. As far as grades, put their letter grades in every week. It could be a little time consuming, but at least you will be able to do it on your time and when you have some free time rather than letting it continue to disrupt your class.
Solution #7
You say that the parents were "constantly" calling but we do not know what "constantly" means to you. This could mean twice a day, everyday, or once a week. I would never discourage parents from contacting me to find out about their child. Third grade is a critical year for retention. This may be playing a role in their anxiety. I would offer to send home a progress report every week if the parents would find that helpful.

From personal experience over protected parents can be extremley horrible for the children.