Kids need to practice to learn, right? So you are going to model how to do it. Then you will probably do a guided lesson where you work on the skill together. Next they will practice the skill and you will walk around and help. Then you may ask them to do it independently like a pre assessment and you check their work. If they did not master the skill you hold a small groups session to reteach or have private conferences with students who need it to clear up any confusion. Finally, you give the assessment and grade that for report card purposes.
Sometimes you have to break a concept down into smaller chunks so it is not all taught at the same time. That way you can get weekly grades in each subject as much as possible.
After the assessment I always did a class average. If the average was in the low 70's or failing I knew I did not do a very good job of teaching the concept. Sometimes I threw those grades away and started over. Other times, most times, I kept the grades and put the topic on my review list for later in the year. There are a few topics that you learn after teaching for a while that will just have lower class averages because they are difficult concepts to grasp.
CENTERS
I like having just three centers or three rotations. But I will say our class count was always 22 or lower. So the number of students you have is a big consideration as you want your groups to be small and productive. Min did many different things before and after meeting me for guided reading.
vocabulary
independent reading
partner reading
answer reading questions
write about reading
In math
play a math game
do practice work on paper
do practice work online
work with manipulatives with an assigned purpose
Good luck in fourth grade. I taught fourth grade for 7 or 8 years. I can't remember which now. They are a great age. You will enjoy how independent they can be and yet still sweet. (most of the time

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