From what I remember, the Universe, in the beginning, was pure energy. Matter couldn't form until it cooled down.
Whoa... you are really
Shaffy, excellent job. Quite above average for middle school.
A little wordy in spots, but that will improve as you write more stuff.
You might want to mention that the Hubble "Constant" has been changed a number of times. When I took a cosmology course back in the early 90's they were using a value about 2/3s of the present value. A number of observations since that time have seemed to zero in the value at around ~69 (km/s) / Mpc. these changes have come about as we have developed new and more effective ways of observing the universe, and been able to gather more data about it.
But if you turn in the paper as is, I think you'll probably get a good grade.