Today, our class and our teacher, Ms. T. took the subway to the High Street Brooklyn Bridge stop .

We started walking from the Brooklyn side of the bridge.

We were getting ready for the trip all week, so, we all had questions we'd thought of that we needed to answer.

My group's question was: "how many cars can the Brooklyn Bridge hold?"

We already knew that we were going to make an estimate , and that we needed to find out how long a car is. But the minute we got there, we saw that there were a lot of different sizes of cars.  So we had to find an average. We measured parked cars .

We came up with 14 feet and 8 inches for the average car length.  Jose and Damian kept measuring the widths of the cars too even though April had already explained to them that the width didn't matter.

It turns out that there are no trucks allowed on the bridge, so we only had to figure out a car length.

It would have made sense to do a weighted average . To do this you would need to watch the cars and vans and count how many of each type go on the bridge.
Then, we found out how many lanes the bridge has, both to and from Brooklyn.  We saw right away that the bridge has 3 lanes going in each direction.  That was easy.

We also needed to find out how long each lane is. This part was hard.  The bridge is really long!  Our tape measure was only 25 feet long, so we thought we would have to use it over and over again, like April said before in class, but then Kamika and I noticed that over the roadway where the cars were, there were these beams . And this part was really cool. We estimated that looking down between two beams, one car could fit! We checked this using our tape measure . The beams were 14 feet apart!  So, since a car was about 14 feet long, on the average, we decided to count the beams on the bridge and figured that one car could fit in the space between two beams.

Then, all we needed to do to figure out how many cars could fit in one long lane was to count the beams .  Then we'd multiply by the number of lanes.  All right!  So we started counting beams.

You did a great job!! But let's think this through a little more in class tomorrow, OK?
While we were counting, we noticed some signs over near the bridge towers that told us that the bridge was originally designed to carry horses, carriages and trolley cars .  We thought that fewer horses and carriages could fit on the bridge than cars.  There wouldn't have been so much traffic in those days, right?

Also, there was a fire on the bridge!   It was in a garbage can.  The guy who sold us water put it out.  He was a hero!  I wonder what would happen if there was a car on fire on the bridge?

From the bridge we saw lots of the buildings in Manhattan like The World Trade Center .  When we got to the Manhattan side, we ate lunch right near City Hall.  Then we went back to our school to talk about our bridge research. That's what Ms. T. says we're doing.

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