See Things to Do on the left and look at the Top Questions on the right including Rainy Day activities and Free Things to do on Cape Cod. Then you can also check www.kidsonthecape.com. But actually weather should be such that you can all enjoy the beach, building sand castles and so forth if not swimming.
If you're interested in bike riding in a safe environment I'd suggest the Cape Cod Rail Trail. I'm not sure where the closest location is to get on that far up the cape, but it should be easy to look up.
I, personally, think that your son is too young for the whale watch. It's a long time on the boat and can be rough. Suggest that you leave that for when he is a few years older.
I was thinking the same thing.
P'town is child friendly because it is so compact and easy to walk around and there is so much interesting going on. You see lots of kids in town. You can rent bikes -- Arnold's is right downtown and may have child seats or trailers. There are bike trails at the edge of town but be aware that the National Seashore classifies some of them as "challenging".
What about going to the beach? Get some sand pails, etc. They love digging or playing ball. It should be warm enough. Just apply sunscreen, add a hat, bring juice and snacks! Sometimes simple is the best for a two year old. Look at the tide pools if possible.Edited: 7:19 pm, August 29, 2012
Truro s beautiful - herring cove beach is probably best - because you can park right at the shore. p-town is fun but no so much for youngster to appreciate,
Hyannis main street, has an arcade and little more kid friendly - chatham has small tours to see seals that might do the trick being they don;t do into deep waters - http://www.monomoyislandferry.com/
the critter cruise aboard the Viking Princess is a fun toddler-friendly activity. You can get that on McMillan pier
And the bus service from Truro to Provincetown is excellent; it runs every 30 minutes until midnight and you can flag the bus down anywhere along the route. Lots of people with fold up baby buggies using it today. From the pier you can catch another bus to Herring Cove.
A great place to spend the day if you enjoy pool life is at the Provincetown In. - the pool opens at 1130am until 5pm and serves really nice food (salads as well as the usual poolside burger type menu). There are always kids there too so perhaps some company for your toddler - and there's as almost private beach area just beyond the pool area.
In fact, it is a really nice walk there from the main bus station in town. I am not sure how long it takes to walk as I keep stopping to look at smart houses I covet, wonderful gardens, fancy little shops, restaurant menus, views down to the sea, coffee (and wifi) at Joe's, not to mention the people watching! I think that, without the distractions, it probably rtakes about 25 minutes - I shall time it tomorrow.
Do not even think about parking at Provincetown as it is hideously expensive and difficult to find!
If you really are serious about some healthy holiday walking, you can walk along the coast road from Truro - there's no pavement but there are plenty of wide grass verges. The traffic is very polite and the cyclists all say hello as they ride past! If you walk in, be sure to follow Commercial Street to see the best of the East End's houses and so as not to miss Angel Foods along that bit of the road to treat yourselves to a really nice sandwich or cake and coffee in recognition of the walking!
And dinner at the Lobster Pot is a must do too. be sure to pick up some Portuguese treats from the Portuguese Bakery along Commercial Street - they do great sandwiches too, but the traditional Portuguese almond cakes and the little egg custard tarts are too good to avoid! There was a Portuguese fishing community in P-Town and the Portuguese heritage lives on in some of the restaurants and influences the menus.Edited: 12:27 am, August 30, 2012
Thanks everyone! I was unaware of the bus service that sounds great instead of parking.