K.,
I know I'm a bit different... but I pick (I don't use clippes to pick them, I'm just careful not to hurt the plant) my pepper whenever I'm hungry for one or need one. Some of them I let turn the other colors (red, purple, yellow orange) depending on what I have planted... right now I have about 8 different kinds of peppers planted - only because I like all the diffent color, shapes, tastes and hot/mildness.
Cucs are a bit different they can get over rip and really bitter. Depending on what kind you planted - striaght 8's get to be 6-10 inches, were as picklers only get about 4-5 inches... I usually pick mine when they look kinda pudgy or nice an full. Don't let them turn yellow or they will be bitter - make sure they are nice and green... unless your like me and plant odd things like Middle Eastern cuc's along with the normal ones.
Most people laugh at my garden - only because I have about 15 kinds of tomatoes, 8 kinds of peppers, 4 kinds of squash, 4 kinds of "green" beens, 4 kinds of cucs, 4 kinds of eggplant along with sweet potatoes, brocclii, cabage, brosel sprouts, and peas. And some of the stuff I plant I don't like - but my neighbors do and they don't like to garden or don't have enought sun to garden... so I plant for them too.
I do want to say you are teaching you little ones a good lesson - and I hope you have fun with it. Every year I try a new kind of plant(s) - this year is sweet potatoes and peas... because it's something new to learn about. Sometimes they work out - sometimes they don't, but it's fun trying.
Enjoy your fresh veggies... there is nothing better then a veggies you plant, grow and pick to put on the table! Home grown always taste better!