Ds got his learners permit yesterday

Let him drive slower, as long as he is not impeding traffic.
It's better than 90 in a 70. Yep,my oldest got pulled for that. She had to do traffic school and the office made her do 10 hours of community service.

It drives me nuts when my DD drives 40 in a 50, but at least she stays in the right lane.  We put a big fat yellow STUDENT DRIVER sticker on the back of the car and it helps keeping the suburban tailgaters off.  What I would give to live in the county with plentiful farm-to-market and oil-top roads for her to practice on.

Deep breaths.  He will get it.

OMG I was the one who had to teach my son to drive! How I did not pull all my hair out, I will never know!

I began to take a book to read in the car or play on my phone so I would not over criticize him when he would do things different that I would have.

Good luck!

I remember those days . Just think about how great it will be when he is finally licensed and can get himself places. 

No it's not! 

DS1 drove about 3 hours total of a 8 hour drive last week (an hour to and 2 hours back). The entire time, he's barely, just barely going 70. I wanted to tell him to go a little faster, just a little bit. But I had to bite my tongue and let DH dish out the best advice - it's better to go the speed limit or a little under while on the learner's permit than to start speeding right off the bat. When I took over driving, I was going almost 80. I wanted to make up for lost time!   Good thing neither teen pays much attention to my driving. As soon as they were in the backseat, they had their noses buried in their phones. 

I wouldn't be making my kid do 50 MPh on his second day of having a permit. He doesn't have the experience to know what to do at that speed if something goes wrong.

My DD is 16 and I'm still not comfortable enough for her to get a license. I have major anxiety every time I drive with her.  We live in a very urban area, think 5 lanes of traffic all speeding 50 with multiple stop lights. I just praise her up and down for not tailgating other drivers and taking her time. I would rather her be too slow than drive too fast.

A whole 6+ hours, eh?

Speed Limits are maximum safe speeds, not minimum. Let him drive at a speed that is comfortable for him and still within the posted safe speed. Now is the time for your DS to develop good driving habits.

Instead of rushing him, take this opportunity to reconsider your own driving habits.

My DS was a pretty good drive, actually very cautious. However, when making a left turn onto a new street and there was a center divider - he would cut the turn and almost hit the divider more times than I could count. I would panic nearly everytime.

Somehow my DH got him to be more mindful about it and he changed the habit. Whew...thank goodness.