Cell phones have a very large and important role in our lives since they open the gates of the world to us. Thanks to them we can easily communicate with each other, find anything online, reach many info and so on. Shortly, it keeps us updated. Therefore, I think it is the biggest type of distraction so I agree that students should not have cell phones in class and I would like to express the reasons behind my statement.
First of all, humankind is a social and curious creature which makes it harder to focus on subjects. Especially at younger ages, we would like to talk to our friends constantly and share various things such as photos, gossip, humor, memes, songs etc. Generally in these ages, it is hard to control our priorities so it is possible to miss a lecture, knowledge or else. We may be don't realize that we are missing something at those times however, it it a well known fact that you only learn lessons when you really focus on your lecture and lecturer. Otherwise, it would be so hard to catch up the next contexts and it gets more difficult in time. Also, we should know that there are plenty of time that you can spent with your friends or your phone. Thus, it should not be a burden to not to bring phone to a class.
Secondly, when students want to solve a question or find a data in class, they usually don't even try to do on their own and they pick up their phone right away which makes them lazier every single day. In order to look up for an answer, it is more significant to try on your own. So that, your ability to solve problems and finding a path to reach a right answer can be developed. Moreover, the communication skills of the students may improve and got better day by day hence, their self confidence gets higher.
Thirdly, there are many kinds and brands of these cell phones and also, not every students have the same life standards. Some students may have the best kind of phones and some may have a very old phones which could be a reason for moral breakdown. As we all know that there are bullying young people and they can not make empathy. In order to prevent these kinds of insensitive behavior, it would be better to not to bring phones to the class.
In a nutshell, students can learn better when they don't have their phones in class so that that could focus simpler. 
Cell  
phones
 have a  
very
 large and  
important
 role in our  
lives
 since they open the gates of the world to us. Thanks to them we can  
easily
 communicate with each other, find anything online, reach  
many info
 and  
so
 on. Shortly, it  
keeps
 us updated.  
Therefore
, I  
think
 it is the biggest type of distraction  
so
 I  
agree
 that  
students
 should not have cell  
phones
 in  
class
 and I would like to express the reasons behind my statement. 
First of all
, humankind is a social and curious creature which  
makes
 it harder to focus on subjects.  
Especially
 at younger ages, we would like to talk to our friends  
constantly
 and share various things such as photos, gossip, humor, memes, songs etc.  
Generally
 in these ages, it is  
hard
 to control our priorities  
so
 it is possible to miss a lecture, knowledge or else. We may be  
don
't realize that we are missing something at those times  
however
,  
it it
 a well known fact that you  
only
 learn lessons when you  
really
 focus on your lecture and lecturer.  
Otherwise
, it would be  
so
  hard
 to catch up the  
next
 contexts and it  
gets
 more difficult in time.  
Also
, we should know that there are  
plenty
 of time that you can  
spent
 with your friends or your  
phone
.  
Thus
, it should not be a burden  
to not to
 bring  
phone
 to a  
class
. 
Secondly
, when  
students
 want to solve a question or find a data in  
class
, they  
usually
 don't even try to do on their  
own and
 they pick up their  
phone
 right away which  
makes
 them lazier every single day. In order to look up for an answer, it is more significant to try on your  
own
.  
So
 that, your ability to solve problems and finding a path to reach a right answer can  
be developed
.  
Moreover
, the communication  
skills
 of the  
students
 may  
improve
 and  
got
 better day by day  
hence
, their  
self confidence
  gets
 higher. 
Thirdly
, there are  
many
 kinds and brands of these cell  
phones
 and  
also
, not every  
students
 have the same life standards.  
Some
  students
 may have the best kind of  
phones
 and  
some
 may have a  
very
  old
  phones
 which could be a reason for moral breakdown. As we all know that there are bullying young  
people and
 they can not  
make
 empathy. In order to  
prevent
 these kinds of insensitive behavior, it would be better  
to not to
 bring  
phones
 to the  
class
.
In a nutshell,  
students
 can learn better when they don't have their  
phones
 in  
class
  so
  that that
 could focus simpler.