What is Steel Tube?
The word tube refers to round, square, rectangular, and oval hollow sections that are used for pressure equipment, for mechanical applications, and for instrumentation systems.
Steel tubing can be made from various raw materials, like iron, carbon, manganese, vanadium, and zirconium. Like pipe, tubing can be produced as either seamless or welded. Seamless tubing is a solid block of steel that is rolled into a round shape and then pierced and stretched into its final length. Think of having a wad of play dough and rolling it into a cylinder. Then push your finger through the middle and make it longer with the extra dough. That’s how it’s produced, but it’s hot and spinning and completely done with machines. Welded steel tubing, on the other hand, is made from the coil. The coil is slit and then rolled up into a round shape and the ends are welded together. From there, the tubing can simply be cut to a certain length as round tubing, or it can be further deformed into other shapes, such as square, rectangular, oval, etc.
What’s the opposite of scaffolding a lesson? Saying to students, “Read this nine-page science article, write a detailed essay on the topic it explores, and turn it in by Wednesday.” Yikes! No safety net, no parachute—they’re just left to their own devices.
Let’s start by agreeing that scaffolding a lesson and differentiating instruction are two different things. Scaffolding is breaking up the learning into chunks and providing a tool, or structure, with each chunk. When scaffolding reading, for example, you might preview the text and discuss key vocabulary, or chunk the text and then read and discuss as you go. With differentiation, you might give a child an entirely different piece of text to read, or shorten the text or alter it, or modify the writing assignment that follows.
Simply put, scaffolding is what you do first with kids. For those students who are still struggling, you may need to differentiate by modifying an assignment or making accommodations like choosing a more accessible text or assigning an alternative project.
Scaffolding and differentiation do have something in common, though. In order to meet students where they are and appropriately scaffold a lesson or differentiate instruction, you have to know the individual and collective zone of proximal development (ZPD) of your learners. Education researcher Eileen Raymond says, “The ZPD is the distance between what children can do by themselves and the next learning that they can be helped to achieve with competent assistance.”
So let’s get to some scaffolding strategies you may or may not have tried yet. Or perhaps you’ve not used them in some time and need a gentle reminder on how awesome and helpful they can be when it comes to student learning.
Riser vs Flat Bars
Riser Vs Flat Bars
We’ve been asked by some riders with bikes with flat handlebars if they should change to riser bars. The large majority of handlebars on mountain bikes are either ‘riser’ or ‘flat’. On downhill and most longer travel bikes (140 mm or more of rear travel) riser bars are prevalent. However, on more racey, cross country style bikes, both riser and flat bars are common.
In this article we’ll examine the difference between the two bars and offer some insight into whether you should consider changing from flat bars to riser bars.
For the purpose of the article, we will assume that the bike in any example given has a stem with little or no rise itself and is not overly short or long. More about stems and how they affect the bike/bars later.
