Answer: It looks like you're supposed to use "mañana también" at the end like they did.
So for question 1, I would write "Vas a andar en patineta mañana también."
For question 2, "Voy a leer un mensaje electrónico mañana también."
It might accept your answers using the pronouns, but their model didn't, so I personally would omit them just to be safe. Like for question 4, your answer looks good aside from the fact that they might not accept "mis abuelos" at the beginning.
