Add lasagna noodles to the water. Boil for 8-10 minutes, stirring continuously for the first 2 minutes to prevent noodles from sticking together. Drain.
While lasagna noodles are cooking, put broccoli into microwave-safe dish, cover and cook for 3 minutes.
Add green onion to broccoli and microwave for another 2 minutes. Drain well.
In another bowl, combine cottage cheese, Parmesan, salt and egg. Add drained broccoli and green onions.
Place the cooked noodles on wax paper. Evenly spread cheese and broccoli mixture on each noodle.
Carefully roll up each noodle.
Using a 9-by-13-inch baking dish, spread about two-thirds of the marinara sauce on the bottom of the dish.
Arrange the rolled noodles in the baking dish with their seams down.
Top with remaining sauce and cover with foil. Bake for 25 minutes.
Remove from oven, pull back foil and sprinkle rolls with mozzarella.
Cover and continue baking for another 10 minutes until cheese melts.